2JZGE Na-T TT Ecu Mod
06-16-20, 09:01 PM
#4126
Driver School Candidate
06-17-20, 05:53 AM
#4127
Idle Problem after NA-T
Good Morning Ali,
I played with the car some more this morning. Here are some things I noticed.
When the car is cold at first start, the idle is about right. As it warms up the idle increases to about 1,500 RPM
If I disconnect the IAC connector, the idle goes up to like 3,000 RPM
I put a multi-meter on the TPS again and noticed that at close (cold engine), the resistance on the IDL pin is 0 and at WOT it goes to open. The problem that I noticed is that it does not go to open when it is cracked a small amount. I have to go to about 1/4" off full close before the circuit opens. I have to take up about 1/4 of slack in the throttle before the IDL goes open.
Here is a link to a very short video of me doing that:
https://drive.google.com/file/d/1fwb...w?usp=drivesdk
I also found that with a hot engine or the engine running, the IDL is open (rather than short) even when the throttle is full closed. I have attached a chart showing the resistance readings I found on the TPS with cold engine, hot engine and engine running. I highlighted the cells that do not look like normal readings.
Do any of these symptoms shed light on my idle problem? I am thinking the IDL going open when hot or when the engine is running might suggest a problem with the TPS. But I am also confused about having to pick up 1/4" play in the throttle before the IDL goes to open when the engine is cold?
Any ideas?
Thanks so much,
Bruce
I played with the car some more this morning. Here are some things I noticed.
When the car is cold at first start, the idle is about right. As it warms up the idle increases to about 1,500 RPM
If I disconnect the IAC connector, the idle goes up to like 3,000 RPM
I put a multi-meter on the TPS again and noticed that at close (cold engine), the resistance on the IDL pin is 0 and at WOT it goes to open. The problem that I noticed is that it does not go to open when it is cracked a small amount. I have to go to about 1/4" off full close before the circuit opens. I have to take up about 1/4 of slack in the throttle before the IDL goes open.
Here is a link to a very short video of me doing that:
https://drive.google.com/file/d/1fwb...w?usp=drivesdk
I also found that with a hot engine or the engine running, the IDL is open (rather than short) even when the throttle is full closed. I have attached a chart showing the resistance readings I found on the TPS with cold engine, hot engine and engine running. I highlighted the cells that do not look like normal readings.
Do any of these symptoms shed light on my idle problem? I am thinking the IDL going open when hot or when the engine is running might suggest a problem with the TPS. But I am also confused about having to pick up 1/4" play in the throttle before the IDL goes to open when the engine is cold?
Any ideas?
Thanks so much,
Bruce
Looks right, at idle the idl pin should be a short or closed, and when the throttle is cracked any amount it should be open like it is.
My guess is that with a new setup, the first couple times you hit some real boost.. it tests all your new hose clamps, couplers, and vac lines.. and I think something came loose or popped off.
either that or the Idle air control valve is sticking in the open position, or even the throttle blade is hanging on carbon buildup but by the tps readings it seems the throttle blade is fine.
So my guess would be that fun pull popped off a hose or intercooler/intake coupler. on a map sensor car an intake manifold leak will show up with a high idle, so I would check there first if it was running pefect before, and if it was idling down to 700 that means it was working perfect and tps was in the right position so I wouldn't mess with the tps or throttle body just yet its probably not that.
My guess is that with a new setup, the first couple times you hit some real boost.. it tests all your new hose clamps, couplers, and vac lines.. and I think something came loose or popped off.
either that or the Idle air control valve is sticking in the open position, or even the throttle blade is hanging on carbon buildup but by the tps readings it seems the throttle blade is fine.
So my guess would be that fun pull popped off a hose or intercooler/intake coupler. on a map sensor car an intake manifold leak will show up with a high idle, so I would check there first if it was running pefect before, and if it was idling down to 700 that means it was working perfect and tps was in the right position so I wouldn't mess with the tps or throttle body just yet its probably not that.
06-17-20, 08:12 AM
#4128
Was there alot of carbon in there when you cleaned it out?
That test seems to indicate the IACV is working at least so that is good.
After that test it seems to be the tps and/or your throttle set screw.
The tps is supposed to be set when engine is fully warmed up, and set so that IDL is "closed" when off the throttle, and somewhere after about 1/8"-1/4" of movement it should go "open".
So yours sounds close to the right tps setting, but it goes out of range when warm, which the play tends to get smaller as it warms up for whatever reason and that part is "normal".
You could try turning back the tps a hair, so that it is in that same range but when fully warmed up, that should let it have better idl control once that pin is activated.
the other issue it could be is that over time someone turned in the throttle body screw to open the throttle body some to make up for a low idle, maybe due to carbon buildup.
Some people that is the first thing they touch and then its out of factory settings for a long time. So if you have the tps adjustment right and still too much air especially after you said you cleaned the throttle body, then you might need to reduce the amount of air coming in by backing off that screw a turn, and then reset the tps so it has that 1/4" play when fully warmed up again.
It is hard to say over the internet and without the full history what is happening, but it is not uncommon to have to adjust the throttle blade set screw and/or the tps when doing the tt ecu mod, and I think alot of times its due to someone over the life of the car having messed with those items before. If they survived 20+ years of being left alone, then they are probably pretty close then.
The other thing to note is that you are supossed to set the timing to 8-10 degrees when the car is fully warmed up and idling (idl pin closed) or you won't get the change in sound when you put the jumper in (you will be looking at full timing instead of base timing then on the crank if you don't hear the sound), so hopefully you set the timing when it was still idling properly. if not double check it when you get the idl pin sorted out.
That test seems to indicate the IACV is working at least so that is good.
After that test it seems to be the tps and/or your throttle set screw.
The tps is supposed to be set when engine is fully warmed up, and set so that IDL is "closed" when off the throttle, and somewhere after about 1/8"-1/4" of movement it should go "open".
So yours sounds close to the right tps setting, but it goes out of range when warm, which the play tends to get smaller as it warms up for whatever reason and that part is "normal".
You could try turning back the tps a hair, so that it is in that same range but when fully warmed up, that should let it have better idl control once that pin is activated.
the other issue it could be is that over time someone turned in the throttle body screw to open the throttle body some to make up for a low idle, maybe due to carbon buildup.
Some people that is the first thing they touch and then its out of factory settings for a long time. So if you have the tps adjustment right and still too much air especially after you said you cleaned the throttle body, then you might need to reduce the amount of air coming in by backing off that screw a turn, and then reset the tps so it has that 1/4" play when fully warmed up again.
It is hard to say over the internet and without the full history what is happening, but it is not uncommon to have to adjust the throttle blade set screw and/or the tps when doing the tt ecu mod, and I think alot of times its due to someone over the life of the car having messed with those items before. If they survived 20+ years of being left alone, then they are probably pretty close then.
The other thing to note is that you are supossed to set the timing to 8-10 degrees when the car is fully warmed up and idling (idl pin closed) or you won't get the change in sound when you put the jumper in (you will be looking at full timing instead of base timing then on the crank if you don't hear the sound), so hopefully you set the timing when it was still idling properly. if not double check it when you get the idl pin sorted out.
Last edited by Ali SC3; 06-17-20 at 08:16 AM.
06-17-20, 08:33 AM
#4129
Ali,
Thanks for your last response. I took a look at the throttle body screw and the paint indicator seems to suggest it has not been touched? I have attached a couple pics below.
Am I looking at the right screw? If so, I should be good there.
As far as the TPS IDL, should it go to open when the car is running and the throttle is not being pushed (so idling)? Or should it stay at shorted like what it should be when the car is not running and the throttle is not being pushed?
Thanks,
Bruce
Thanks for your last response. I took a look at the throttle body screw and the paint indicator seems to suggest it has not been touched? I have attached a couple pics below.
Am I looking at the right screw? If so, I should be good there.
As far as the TPS IDL, should it go to open when the car is running and the throttle is not being pushed (so idling)? Or should it stay at shorted like what it should be when the car is not running and the throttle is not being pushed?
Thanks,
Bruce
06-17-20, 03:44 PM
#4130
IDL should be closed when idling (not pressing throttle) and should be open when you do press on the throttle. it should be set so it takes a little bit of throttle before it goes "open".
That way anytime the ecu sees IDL closed, it knows you are not pressing the gas and trying to idle.
Assuming the screw is in the right spot already, it could be you need more slack in the throttle cable and it is not letting the throttle rest fully against the stop.
You can adjust it by the 2 nuts on the throttle cable, if the cable is too tight it can hang up and not let it close all the way.
It's easy to make that mistake if you remove the cable for servicing, just make sure it has some slack in it when you tighten it down.
I have heard members say they had to tweak the tps and/or step stop screw, even if it was stock just depends on the setup and what is going on.
It seems it was at 700 before, so it sounds like it is something temporary is happening and I can't pin point it based on that, so you probably have to look around and see if anything is out of place.
Also check the IACV connector, those are common to crack and then the iacv will do wierd stuff, almost always after you take the throttle body off and put it back on the connector sometimes will be just loose enough to not let all the different stepper motors of the IACV work.
That way anytime the ecu sees IDL closed, it knows you are not pressing the gas and trying to idle.
Assuming the screw is in the right spot already, it could be you need more slack in the throttle cable and it is not letting the throttle rest fully against the stop.
You can adjust it by the 2 nuts on the throttle cable, if the cable is too tight it can hang up and not let it close all the way.
It's easy to make that mistake if you remove the cable for servicing, just make sure it has some slack in it when you tighten it down.
I have heard members say they had to tweak the tps and/or step stop screw, even if it was stock just depends on the setup and what is going on.
It seems it was at 700 before, so it sounds like it is something temporary is happening and I can't pin point it based on that, so you probably have to look around and see if anything is out of place.
Also check the IACV connector, those are common to crack and then the iacv will do wierd stuff, almost always after you take the throttle body off and put it back on the connector sometimes will be just loose enough to not let all the different stepper motors of the IACV work.
06-18-20, 04:32 AM
#4132
High Idle Issue Solved
Ali,
I decided to try and turn the TPS a hair counter clockwise to slow the idle down a bit. First, I used a scribe to put a mark on the throttle body and one on the TPS itself so I knew where I started. Then I turned it 1 degree or less counter clockwise, snugged the screws, and re-checked my TPS resistance values.
Prior to the change, my closed throttle E2-IDL measurement with the engine cold was 0.00kΩ (short). With the engine hot or running, it was open circuit.
After the change, my closed throttle E2-IDL measurement with the engine cold is 0.00kΩ (short). With the engine hot or running it is also 0.00kΩ (short). In both cases before and after the change in TPS position, my E2-IDL resistance was/is 3.96kΩ at WOT.
Fixed! With this, my idle is now right at 700RPM or so (cold and hot).
I adjusted my timing and BAM good to go. I took it for a ride with some good pulls and it still comes right back to normal idle.
Thanks so much for your help.
Bruce
I decided to try and turn the TPS a hair counter clockwise to slow the idle down a bit. First, I used a scribe to put a mark on the throttle body and one on the TPS itself so I knew where I started. Then I turned it 1 degree or less counter clockwise, snugged the screws, and re-checked my TPS resistance values.
Prior to the change, my closed throttle E2-IDL measurement with the engine cold was 0.00kΩ (short). With the engine hot or running, it was open circuit.
After the change, my closed throttle E2-IDL measurement with the engine cold is 0.00kΩ (short). With the engine hot or running it is also 0.00kΩ (short). In both cases before and after the change in TPS position, my E2-IDL resistance was/is 3.96kΩ at WOT.
Fixed! With this, my idle is now right at 700RPM or so (cold and hot).
I adjusted my timing and BAM good to go. I took it for a ride with some good pulls and it still comes right back to normal idle.
Thanks so much for your help.
Bruce
IDL should be closed when idling (not pressing throttle) and should be open when you do press on the throttle. it should be set so it takes a little bit of throttle before it goes "open".
That way anytime the ecu sees IDL closed, it knows you are not pressing the gas and trying to idle.
Assuming the screw is in the right spot already, it could be you need more slack in the throttle cable and it is not letting the throttle rest fully against the stop.
You can adjust it by the 2 nuts on the throttle cable, if the cable is too tight it can hang up and not let it close all the way.
It's easy to make that mistake if you remove the cable for servicing, just make sure it has some slack in it when you tighten it down.
I have heard members say they had to tweak the tps and/or step stop screw, even if it was stock just depends on the setup and what is going on.
It seems it was at 700 before, so it sounds like it is something temporary is happening and I can't pin point it based on that, so you probably have to look around and see if anything is out of place.
Also check the IACV connector, those are common to crack and then the iacv will do wierd stuff, almost always after you take the throttle body off and put it back on the connector sometimes will be just loose enough to not let all the different stepper motors of the IACV work.
That way anytime the ecu sees IDL closed, it knows you are not pressing the gas and trying to idle.
Assuming the screw is in the right spot already, it could be you need more slack in the throttle cable and it is not letting the throttle rest fully against the stop.
You can adjust it by the 2 nuts on the throttle cable, if the cable is too tight it can hang up and not let it close all the way.
It's easy to make that mistake if you remove the cable for servicing, just make sure it has some slack in it when you tighten it down.
I have heard members say they had to tweak the tps and/or step stop screw, even if it was stock just depends on the setup and what is going on.
It seems it was at 700 before, so it sounds like it is something temporary is happening and I can't pin point it based on that, so you probably have to look around and see if anything is out of place.
Also check the IACV connector, those are common to crack and then the iacv will do wierd stuff, almost always after you take the throttle body off and put it back on the connector sometimes will be just loose enough to not let all the different stepper motors of the IACV work.
Last edited by bbyatv; 06-18-20 at 04:37 AM. Reason: Spelling
06-18-20, 06:39 AM
#4133
Acis/aciv
Ali,
If you plumb the ACIS/ACIV straight to vacuum, would the actuator then behave as though the ECU is cutting vacuum when the system sees boost (i.e. the vacuum to the actuator goes away)? Would the intake manifold run then be shortened (with the valve open) when you want it to be long? It would seem you want vacuum to the actuator at all times (even in boost) or just some how mechanically fix the valve so it is closed all the time (longer manifold run)?
Am I mis-understanding the way the system works?
Thanks,
Bruce
If you plumb the ACIS/ACIV straight to vacuum, would the actuator then behave as though the ECU is cutting vacuum when the system sees boost (i.e. the vacuum to the actuator goes away)? Would the intake manifold run then be shortened (with the valve open) when you want it to be long? It would seem you want vacuum to the actuator at all times (even in boost) or just some how mechanically fix the valve so it is closed all the time (longer manifold run)?
Am I mis-understanding the way the system works?
Thanks,
Bruce
Nope I pulled those because the gte ecu does not trigger the vsv's at the same time the ge ecu does.
I plumbed it directly to a vacuum source.
basically the stock setup is only different that it cuts the vacuum out at idle and lower throttle so you don't get the extra performance = save gas and a little smoother. without the VSV its like 100% performance mode so I wasn't about to figure out how to get the vsv working like stock I rather have the power on tap at all times.
I plumbed it directly to a vacuum source.
basically the stock setup is only different that it cuts the vacuum out at idle and lower throttle so you don't get the extra performance = save gas and a little smoother. without the VSV its like 100% performance mode so I wasn't about to figure out how to get the vsv working like stock I rather have the power on tap at all times.
06-18-20, 08:48 AM
#4134
You want long runner off of idle where the air demand is lower and the extra velocity of the long runner gives you more torque.
That works well up to about mid way through the power band, where the long runner becomes a restriction and starts to make less power than a short/open runner.
That mostly happens because of the higher engine speed needing a larger volume of air that it can't just pull from one side of the intake, so basically demand for air outweighs the velocity of the incoming air in this situation, so it goes to short runner which has double the plenum volume but less velocity (if you are turbo you are cramming the air in in boost so the velocity isn't as big a deal).
So the idea is you want long runner down low to boost torque, then switch over to open/short runner when the engine needs that extra air.
That is why they put the ACIS on the GE to take advantage of the torque down low.
The main difference between the ecu controlling it and connected straight to vacuum, is that the ecu control has a canister that stores vacuum and a vsv so it can turn it on and off in situations that don't follow the actual vacuum, and it does that when cruising. normally due to vacuum you would have long runner in cruise with it straight connected to vacuum, but the ecu will actually cut it off and keep you in short runner for cruise cause it is smoother (I couldn't tell a huge difference to be honest, just going off the literature says).
All the other times the ecu will mimick what the vacuum is actually doing, just not in cruise. the good news is you can cruise with long runners just fine, did it for many years no issues and feels more responsive when you step on it from cruise. The other slight difference is with the canister it can hold it longer, but with a turbo you don't want it longer you just want it off idle and into your spooling rpm.
If you notice, the GTE has a full time short runner and has no ACIS. the small twins more than makes up for any down low loss due to short runner, but with a larger single turbo it is a good idea to leave it in place on a GE setup cause it will give you a torque boost till about 3500 rpm's or so which helps spool out significantly.
There was a chart somewhere I posted showing the conditions for the stock ecu triggering it, and the main difference was cruise.
So having it hooked up direct to vacuum bypassing all the stuff, you will get long runner at lower rpm's and when you are starting to boost and loose vacuum it will go to a short runner, which is literally perfect. I also had it hooked up the stock way through an aem ems controlling the on and off points, and the seat of pants dyno was similar in both cases, and both felt faster than having ACIS removed. If one wanted to build a crazy low end torque monster, it would involve using ACIS, VVTI and a small single turbo as they would all work together to improve spool.
That works well up to about mid way through the power band, where the long runner becomes a restriction and starts to make less power than a short/open runner.
That mostly happens because of the higher engine speed needing a larger volume of air that it can't just pull from one side of the intake, so basically demand for air outweighs the velocity of the incoming air in this situation, so it goes to short runner which has double the plenum volume but less velocity (if you are turbo you are cramming the air in in boost so the velocity isn't as big a deal).
So the idea is you want long runner down low to boost torque, then switch over to open/short runner when the engine needs that extra air.
That is why they put the ACIS on the GE to take advantage of the torque down low.
The main difference between the ecu controlling it and connected straight to vacuum, is that the ecu control has a canister that stores vacuum and a vsv so it can turn it on and off in situations that don't follow the actual vacuum, and it does that when cruising. normally due to vacuum you would have long runner in cruise with it straight connected to vacuum, but the ecu will actually cut it off and keep you in short runner for cruise cause it is smoother (I couldn't tell a huge difference to be honest, just going off the literature says).
All the other times the ecu will mimick what the vacuum is actually doing, just not in cruise. the good news is you can cruise with long runners just fine, did it for many years no issues and feels more responsive when you step on it from cruise. The other slight difference is with the canister it can hold it longer, but with a turbo you don't want it longer you just want it off idle and into your spooling rpm.
If you notice, the GTE has a full time short runner and has no ACIS. the small twins more than makes up for any down low loss due to short runner, but with a larger single turbo it is a good idea to leave it in place on a GE setup cause it will give you a torque boost till about 3500 rpm's or so which helps spool out significantly.
There was a chart somewhere I posted showing the conditions for the stock ecu triggering it, and the main difference was cruise.
So having it hooked up direct to vacuum bypassing all the stuff, you will get long runner at lower rpm's and when you are starting to boost and loose vacuum it will go to a short runner, which is literally perfect. I also had it hooked up the stock way through an aem ems controlling the on and off points, and the seat of pants dyno was similar in both cases, and both felt faster than having ACIS removed. If one wanted to build a crazy low end torque monster, it would involve using ACIS, VVTI and a small single turbo as they would all work together to improve spool.
The following users liked this post:
mrmj2u (06-18-20)
06-18-20, 09:01 AM
#4135
Ahhh. I was just mis understanding when you want a long vs. short runner. What I take from your post below is long runner is good at low RPM and short runner is good at higher RPM. In that case a vacuum line straight to ACIS actuator makes sense.
Thanks,
Bruce
Thanks,
Bruce
You want long runner off of idle where the air demand is lower and the extra velocity of the long runner gives you more torque.
That works well up to about mid way through the power band, where the long runner becomes a restriction and starts to make less power than a short/open runner.
That mostly happens because of the higher engine speed needing a larger volume of air that it can't just pull from one side of the intake, so basically demand for air outweighs the velocity of the incoming air in this situation, so it goes to short runner which has double the plenum volume but less velocity (if you are turbo you are cramming the air in in boost so the velocity isn't as big a deal).
So the idea is you want long runner down low to boost torque, then switch over to open/short runner when the engine needs that extra air.
That is why they put the ACIS on the GE to take advantage of the torque down low.
The main difference between the ecu controlling it and connected straight to vacuum, is that the ecu control has a canister that stores vacuum and a vsv so it can turn it on and off in situations that don't follow the actual vacuum, and it does that when cruising. normally due to vacuum you would have long runner in cruise with it straight connected to vacuum, but the ecu will actually cut it off and keep you in short runner for cruise cause it is smoother (I couldn't tell a huge difference to be honest, just going off the literature says).
All the other times the ecu will mimick what the vacuum is actually doing, just not in cruise. the good news is you can cruise with long runners just fine, did it for many years no issues and feels more responsive when you step on it from cruise. The other slight difference is with the canister it can hold it longer, but with a turbo you don't want it longer you just want it off idle and into your spooling rpm.
If you notice, the GTE has a full time short runner and has no ACIS. the small twins more than makes up for any down low loss due to short runner, but with a larger single turbo it is a good idea to leave it in place on a GE setup cause it will give you a torque boost till about 3500 rpm's or so which helps spool out significantly.
There was a chart somewhere I posted showing the conditions for the stock ecu triggering it, and the main difference was cruise.
So having it hooked up direct to vacuum bypassing all the stuff, you will get long runner at lower rpm's and when you are starting to boost and loose vacuum it will go to a short runner, which is literally perfect. I also had it hooked up the stock way through an aem ems controlling the on and off points, and the seat of pants dyno was similar in both cases, and both felt faster than having ACIS removed. If one wanted to build a crazy low end torque monster, it would involve using ACIS, VVTI and a small single turbo as they would all work together to improve spool.
That works well up to about mid way through the power band, where the long runner becomes a restriction and starts to make less power than a short/open runner.
That mostly happens because of the higher engine speed needing a larger volume of air that it can't just pull from one side of the intake, so basically demand for air outweighs the velocity of the incoming air in this situation, so it goes to short runner which has double the plenum volume but less velocity (if you are turbo you are cramming the air in in boost so the velocity isn't as big a deal).
So the idea is you want long runner down low to boost torque, then switch over to open/short runner when the engine needs that extra air.
That is why they put the ACIS on the GE to take advantage of the torque down low.
The main difference between the ecu controlling it and connected straight to vacuum, is that the ecu control has a canister that stores vacuum and a vsv so it can turn it on and off in situations that don't follow the actual vacuum, and it does that when cruising. normally due to vacuum you would have long runner in cruise with it straight connected to vacuum, but the ecu will actually cut it off and keep you in short runner for cruise cause it is smoother (I couldn't tell a huge difference to be honest, just going off the literature says).
All the other times the ecu will mimick what the vacuum is actually doing, just not in cruise. the good news is you can cruise with long runners just fine, did it for many years no issues and feels more responsive when you step on it from cruise. The other slight difference is with the canister it can hold it longer, but with a turbo you don't want it longer you just want it off idle and into your spooling rpm.
If you notice, the GTE has a full time short runner and has no ACIS. the small twins more than makes up for any down low loss due to short runner, but with a larger single turbo it is a good idea to leave it in place on a GE setup cause it will give you a torque boost till about 3500 rpm's or so which helps spool out significantly.
There was a chart somewhere I posted showing the conditions for the stock ecu triggering it, and the main difference was cruise.
So having it hooked up direct to vacuum bypassing all the stuff, you will get long runner at lower rpm's and when you are starting to boost and loose vacuum it will go to a short runner, which is literally perfect. I also had it hooked up the stock way through an aem ems controlling the on and off points, and the seat of pants dyno was similar in both cases, and both felt faster than having ACIS removed. If one wanted to build a crazy low end torque monster, it would involve using ACIS, VVTI and a small single turbo as they would all work together to improve spool.
07-07-20, 04:22 AM
#4137
Hundreds of Detailed Pics of 2JZ Re-Build and NA-T Turbo Install
I created a folder with hundreds of detailed pictures of my 2JZ re-build before during and after we tore it down, re-built it, and added a turbo.
If you are working on yours and forgot how a line runs or a part goes on, there is likely a picture of it in this folder.
Hope it helps.
https://drive.google.com/drive/folde...F2?usp=sharing
Bruce
If you are working on yours and forgot how a line runs or a part goes on, there is likely a picture of it in this folder.
Hope it helps.
https://drive.google.com/drive/folde...F2?usp=sharing
Bruce
07-23-20, 11:26 AM
#4138
Driver School Candidate
Join Date: Jul 2020
Location: TX
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Thank you very much for this thread! Awesome Upgrade. I do have some questions however in regards to vvti doing this mod. I did see user "sc3rrt" was attempting this in his sc300, but looked like he had to do some extensive wiring as well that he got from Grubbs? build page.
I'm getting tons of mixed answers and I'd just like a little clarification.
2JZGE VVTi - GS300 wiring harness
JDM VVTi Ecu
JDM MAF sensor
2JZ MAP sensor
440cc injectors
1. Plug JDM MAF in like normal (no wiring needed)
2. Plug in MAP sensor (+5v lead & sensor ground spliced into TPS +5v & sensor Ground / Map signal wire to ECU Plug B2 Pin 9 - Pressure Intake Manifold (PIM)
3. Pop in 400cc 7M injectors with resistor pack
Is there more wiring I need to do to get this to work? I'm on the FB forums and one guy said he had his setup running like this for a while with no issues, no other wiring going on but kind of had to believe when sc3rrt was posting tons of other wiring diagrams?
Thank you so much for your time and help.
I'm getting tons of mixed answers and I'd just like a little clarification.
2JZGE VVTi - GS300 wiring harness
JDM VVTi Ecu
JDM MAF sensor
2JZ MAP sensor
440cc injectors
1. Plug JDM MAF in like normal (no wiring needed)
2. Plug in MAP sensor (+5v lead & sensor ground spliced into TPS +5v & sensor Ground / Map signal wire to ECU Plug B2 Pin 9 - Pressure Intake Manifold (PIM)
3. Pop in 400cc 7M injectors with resistor pack
Is there more wiring I need to do to get this to work? I'm on the FB forums and one guy said he had his setup running like this for a while with no issues, no other wiring going on but kind of had to believe when sc3rrt was posting tons of other wiring diagrams?
Thank you so much for your time and help.
07-23-20, 02:01 PM
#4139
I don't know that the gs300 has the same connector for all the years of gs300 vvti, you will have to compare the connector yourself to see if it the same, lots of pictures online of the 2jzgte vvti connector. I know the is300 only had the vvti 2jzgte connector for 2001, and 2002 onwards it has the new connector which requires a complete re-wire, so double check.
steps 1-2 look correct, step 3 I would honestly avoid the 7m injectors with resistor pack, get some high impedance 440's that will drop in, check oside tiger they usually have sets of 440 available and aren't expensive. rewiring a vvti harness for a resistor pack is a waste and adding in extra heat and points of failure etc...
I can't remember all the little stuff that needed to be done or what he posted, lots of posts in here from lots of members. ensure o2 sensors and all the big stuff are going to the same spots, it should run for the most part minus any differences from the specific chassis (GS vs SC). I have not done it personally but everyone has different issues, sometimes they are just a bad part and not wiring, sometimes it the other way or both, hard to say. I think if you had no bad parts and nailed the wiring it would start and run.
I think there is also an issue with the a/c working when using the aristo vvti ecu, it doesn't have the same setup as the supra vvti ecu which is more plug and play in a SC.
For a GS I am not sure at all, maybe the aristo ecu could operate the ecu I think part of it is over canbus on those models, wouldn't count on it though. likely will need to have a workaround for the a/c which was discussed a little while ago on here, and gets it to turn on but I think it bypasses the ecu being able to control it.
With the vvti it is not as commonly done so be prepared for moving some additional wires around especially on a GS. I don't think it will be a huge deal though, should be able to get it running and driving. You may also run into issues with the transmission, I think gerrb used a gte auto and I can't remember if wiring needs to be done for that.. but I would look into that or a manual swap your vti ge auto trans wont last very long above 400hp.
steps 1-2 look correct, step 3 I would honestly avoid the 7m injectors with resistor pack, get some high impedance 440's that will drop in, check oside tiger they usually have sets of 440 available and aren't expensive. rewiring a vvti harness for a resistor pack is a waste and adding in extra heat and points of failure etc...
I can't remember all the little stuff that needed to be done or what he posted, lots of posts in here from lots of members. ensure o2 sensors and all the big stuff are going to the same spots, it should run for the most part minus any differences from the specific chassis (GS vs SC). I have not done it personally but everyone has different issues, sometimes they are just a bad part and not wiring, sometimes it the other way or both, hard to say. I think if you had no bad parts and nailed the wiring it would start and run.
I think there is also an issue with the a/c working when using the aristo vvti ecu, it doesn't have the same setup as the supra vvti ecu which is more plug and play in a SC.
For a GS I am not sure at all, maybe the aristo ecu could operate the ecu I think part of it is over canbus on those models, wouldn't count on it though. likely will need to have a workaround for the a/c which was discussed a little while ago on here, and gets it to turn on but I think it bypasses the ecu being able to control it.
With the vvti it is not as commonly done so be prepared for moving some additional wires around especially on a GS. I don't think it will be a huge deal though, should be able to get it running and driving. You may also run into issues with the transmission, I think gerrb used a gte auto and I can't remember if wiring needs to be done for that.. but I would look into that or a manual swap your vti ge auto trans wont last very long above 400hp.
07-23-20, 02:25 PM
#4140
Driver School Candidate
Join Date: Jul 2020
Location: TX
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
I don't know that the gs300 has the same connector for all the years of gs300 vvti, you will have to compare the connector yourself to see if it the same, lots of pictures online of the 2jzgte vvti connector. I know the is300 only had the vvti 2jzgte connector for 2001, and 2002 onwards it has the new connector which requires a complete re-wire, so double check.
steps 1-2 look correct, step 3 I would honestly avoid the 7m injectors with resistor pack, get some high impedance 440's that will drop in, check oside tiger they usually have sets of 440 available and aren't expensive. rewiring a vvti harness for a resistor pack is a waste and adding in extra heat and points of failure etc...
I can't remember all the little stuff that needed to be done or what he posted, lots of posts in here from lots of members. ensure o2 sensors and all the big stuff are going to the same spots, it should run for the most part minus any differences from the specific chassis (GS vs SC). I have not done it personally but everyone has different issues, sometimes they are just a bad part and not wiring, sometimes it the other way or both, hard to say. I think if you had no bad parts and nailed the wiring it would start and run.
I think there is also an issue with the a/c working when using the aristo vvti ecu, it doesn't have the same setup as the supra vvti ecu which is more plug and play in a SC.
For a GS I am not sure at all, maybe the aristo ecu could operate the ecu I think part of it is over canbus on those models, wouldn't count on it though. likely will need to have a workaround for the a/c which was discussed a little while ago on here, and gets it to turn on but I think it bypasses the ecu being able to control it.
With the vvti it is not as commonly done so be prepared for moving some additional wires around especially on a GS. I don't think it will be a huge deal though, should be able to get it running and driving. You may also run into issues with the transmission, I think gerrb used a gte auto and I can't remember if wiring needs to be done for that.. but I would look into that or a manual swap your vti ge auto trans wont last very long above 400hp.
steps 1-2 look correct, step 3 I would honestly avoid the 7m injectors with resistor pack, get some high impedance 440's that will drop in, check oside tiger they usually have sets of 440 available and aren't expensive. rewiring a vvti harness for a resistor pack is a waste and adding in extra heat and points of failure etc...
I can't remember all the little stuff that needed to be done or what he posted, lots of posts in here from lots of members. ensure o2 sensors and all the big stuff are going to the same spots, it should run for the most part minus any differences from the specific chassis (GS vs SC). I have not done it personally but everyone has different issues, sometimes they are just a bad part and not wiring, sometimes it the other way or both, hard to say. I think if you had no bad parts and nailed the wiring it would start and run.
I think there is also an issue with the a/c working when using the aristo vvti ecu, it doesn't have the same setup as the supra vvti ecu which is more plug and play in a SC.
For a GS I am not sure at all, maybe the aristo ecu could operate the ecu I think part of it is over canbus on those models, wouldn't count on it though. likely will need to have a workaround for the a/c which was discussed a little while ago on here, and gets it to turn on but I think it bypasses the ecu being able to control it.
With the vvti it is not as commonly done so be prepared for moving some additional wires around especially on a GS. I don't think it will be a huge deal though, should be able to get it running and driving. You may also run into issues with the transmission, I think gerrb used a gte auto and I can't remember if wiring needs to be done for that.. but I would look into that or a manual swap your vti ge auto trans wont last very long above 400hp.
Good point in bringing up the A/C issue as the Aristo TT ecu does not have the A/C signal input whereas the JDM JZ80 vvti TT ecu does have the A/C input signal. Going with the JZ80 JDM TT ecu would be awesome for me and my swap (GE in BMW E46), however just found out that DBW delete is not going to work with the stock ECU and need to convert to regular accelerator cable, so the vvti head is now out of the question.
For now, plans have changed to go with 2JZGE non-vvti as this does not have DBW, and DOES have A/C Input request pin on the ECU. I will run NA-T on the stock ECU for a bit until I can get my hands on a TT ecu and then complete this mod
Thank you again so much for taking the time to reply and to post this awesome mod.