1JZ Single SC400 bucking and irregular idle
#31
1JZ Single SC400
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I had about an hour to check a few things. I did clean the IACV filter and housing. It was jet black in there, and blew it out with compressed air. It still ran the same with the surging at idle. I will hook this up to the AEM this weekend and post my results. I did call the local tuner, and told him my symptoms, and believe it or not, I was actually blown away at the way he thought the AEM should be tuned and his explanation of the IACV and TPS working together. I set an appointment up with him on Tuesday morning. I hope we can possibly get it together.
Quick I haven't forgotten about you and the email. I have been really busy here.
I also hopefully found my oil leak. I removed the center cover and found a little bit of oil around the valve covers in the rear. I assume this is where my oil leak is coming from. All along I was thinking it was the rear main, which it still could be. I cleaned everything really good under the car, and on top with brake cleaner, then dried with compressed air. The four bolts on both sides in the rear, were actually loose. I re torqued them back down with even pressure. i will recheck the oil leak in a few days and see if any has come back.
Quick I haven't forgotten about you and the email. I have been really busy here.
I also hopefully found my oil leak. I removed the center cover and found a little bit of oil around the valve covers in the rear. I assume this is where my oil leak is coming from. All along I was thinking it was the rear main, which it still could be. I cleaned everything really good under the car, and on top with brake cleaner, then dried with compressed air. The four bolts on both sides in the rear, were actually loose. I re torqued them back down with even pressure. i will recheck the oil leak in a few days and see if any has come back.
#33
1JZ Single SC400
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I went by the local tuner today and he welcomed me with a lot of knowledge. He seemed to me that he knew his stuff. He noticed the idling problem as soon as I cranked the car. He tweaked with the settings for about 30 minutes, and then we went on a test drive. He made some adjustments on the idle even more with the AC on and to the IACV. We couldn't get it to die for any reason, unlike before. He seemed to think that the size injectors might be the corporate. He felt they needed to run super rich around 10.3-11.3 to run without any miss, or hiccups. He recommended top feed injectors and a retune, if I deemed it necessary. The bottom line is that it runs more efficient at idle and the AC problem is fixed. We will see how long this stays pretty close and running better.
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But i am glad you got it working properly.
Yes i would sell those side feed injectors and get some ID1000 with a top feed fuel rail and you are golden! That's what i would do if i were you .
#37
1JZ Single SC400
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Thanks for allowing him to review it and see what he thinks. Overall the car feels and sounds much better with the idle and AC on. NO dying as of today. So far so good. Thats exactly what the local guy recommended on the injectors as well. Small world.. LOL
I have no cats whatsoever. Just straight pipe from DP back.. No worries in the state of Bama.
I have no cats whatsoever. Just straight pipe from DP back.. No worries in the state of Bama.
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800cc injectors shouldn't be hard to tune unless there is something wrong with them. I've tuned regular 850's on a map-ecu 1 with no problem. There might be some other underlying issues with the car. Do you have the check engine light hooked up? Maybe check the vacuum hose to the map sensor, and make sure it's reading correctly should be -20 at idle.
I had to gap my NGK 4644's to .022 on stock twins. I'm running 550cc injectors and it idles perfectly at 14.7-15, even though I recently found out my knock sensor wire was bad throwing a code 52. I use MAP-ECU 2, cuz it's easy for me to tune myself.
There is no reason the car shouldn't run perfectly and idle correctly at 14.7, there's either something wrong or not tuned correctly.
I had to gap my NGK 4644's to .022 on stock twins. I'm running 550cc injectors and it idles perfectly at 14.7-15, even though I recently found out my knock sensor wire was bad throwing a code 52. I use MAP-ECU 2, cuz it's easy for me to tune myself.
There is no reason the car shouldn't run perfectly and idle correctly at 14.7, there's either something wrong or not tuned correctly.
#39
1JZ Single SC400
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You are prolly right on one of the issues. I have emailed Quick the AEM file for his tuner to review. If Quick thinks it needs a re tune, then that is what we will more than likely due.
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No 800cc will not be hard to tune if the tuner knows what he is doing or how to set things up.
He bought the injectors used , so they could use some cleaning!
I wouldn't gap my plugs lower than .28, you either need a DLi or New coils.
AEM EMS doesn't trip a Check Engine Light.
He bought the injectors used , so they could use some cleaning!
I wouldn't gap my plugs lower than .28, you either need a DLi or New coils.
AEM EMS doesn't trip a Check Engine Light.
#41
1JZ Single SC400
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I found a new set of coils here local for 100. I will pick them up next week just for the sake of having a piece of mind. I am also going to change the plugs again, due to being cheap and inexpensive. I am going to use NGK copper ones.
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800cc injectors shouldn't be hard to tune unless there is something wrong with them. I've tuned regular 850's on a map-ecu 1 with no problem. There might be some other underlying issues with the car. Do you have the check engine light hooked up? Maybe check the vacuum hose to the map sensor, and make sure it's reading correctly should be -20 at idle.
I had to gap my NGK 4644's to .022 on stock twins. I'm running 550cc injectors and it idles perfectly at 14.7-15, even though I recently found out my knock sensor wire was bad throwing a code 52. I use MAP-ECU 2, cuz it's easy for me to tune myself.
There is no reason the car shouldn't run perfectly and idle correctly at 14.7, there's either something wrong or not tuned correctly.
I had to gap my NGK 4644's to .022 on stock twins. I'm running 550cc injectors and it idles perfectly at 14.7-15, even though I recently found out my knock sensor wire was bad throwing a code 52. I use MAP-ECU 2, cuz it's easy for me to tune myself.
There is no reason the car shouldn't run perfectly and idle correctly at 14.7, there's either something wrong or not tuned correctly.
OP: I'm assuming the sard injectors are what you're running. Anyway you could find the latency/battery offset info somewhere and compare with what the tuner setup? From what you say after Omar had Brad look over the file, sounds like the tune is the problem. Stock ecu cars are usually easier to deal with because the ecu helps you diagnose, but with the standalone stuff you're on your own and experience seems to be the key.
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^^^ This guy knows his stuff.
I would never run less than .28. In fact with my old vvti coil setup i was at .033 iirc and .044 with my Lq9 Coils at 24 psi.
I have seen people run .44 gap and 50psi on 91mm Turbo with the Lq9 coils on E85 with zero break up!
Scott on here runs 32 psi with the vvti coils almost 900whp for years.
Remember these coils are over 20years old, and alot people don't know how much power they are losing running these old Coils.
Alpha at IP did a test on used stock coils and brand new toyota coils and the results were unbelievable, it was on FB at some point.
I just talk to brand and he is remote tuning , so tonight or tomorrow by the end of the day i will have some answers for you Mark!
Edit
Mark,
Do you still have your dyno sheet? if you do can you post it up please if you don't mind.
I would never run less than .28. In fact with my old vvti coil setup i was at .033 iirc and .044 with my Lq9 Coils at 24 psi.
I have seen people run .44 gap and 50psi on 91mm Turbo with the Lq9 coils on E85 with zero break up!
Scott on here runs 32 psi with the vvti coils almost 900whp for years.
Remember these coils are over 20years old, and alot people don't know how much power they are losing running these old Coils.
Alpha at IP did a test on used stock coils and brand new toyota coils and the results were unbelievable, it was on FB at some point.
I just talk to brand and he is remote tuning , so tonight or tomorrow by the end of the day i will have some answers for you Mark!
Edit
Mark,
Do you still have your dyno sheet? if you do can you post it up please if you don't mind.
Last edited by 99SC42; 05-08-13 at 06:30 PM.
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I read alot of other people having to gap really low on the stock coils with the 1J and figured it was relatively normal. In my supra I ran 30PSI on a 70mm turbo gapped at .026 with the stock coils, obviously not the best, but it worked. I guess it's "normal" due to the age of the stock coils and them needing replacement. It could also have to do with my ecu running in limp mode with the broken knock sensor connector. I didn't think about coils because the car has been running "well", at this power level anyways. I just found out it was throwing code 52 a couple days ago. I road race the car, 6 track days in the last 2 months, and have been keeping up/whooping up on fast cars, I know it's making at-least 350rwhp, even with the pulled timing.
Luckily it's not daily driven, only to the track and back.
I'm sure it would be at 400rwhp with good coils and aggressive timing, not to mention better mpg. Anyways, thanks guys for the info, because I have so many things I adjust on the car every day, it's hard to keep track of what it needs.
Here's a pic with my ugly bumper, lol
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I'm sure it would be at 400rwhp with good coils and aggressive timing, not to mention better mpg. Anyways, thanks guys for the info, because I have so many things I adjust on the car every day, it's hard to keep track of what it needs.
Here's a pic with my ugly bumper, lol
http://imageshack.us/a/img17/812/img20130505174249.jpg
Last edited by fried_rice; 05-08-13 at 07:26 PM.
#45
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you may want to try the iridiums instead of the coppers, they will spark better for longer.
something like a bkr7eix or bkr8eix depending on how much boost you run, they come gapped at .032 I just drop them in usually without any regapping. the ones with a -11 on the end are .042 gap you don't want those unless you have some beefy coils or run low boost all the time.
something like a bkr7eix or bkr8eix depending on how much boost you run, they come gapped at .032 I just drop them in usually without any regapping. the ones with a -11 on the end are .042 gap you don't want those unless you have some beefy coils or run low boost all the time.
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