sc300 w/ 2jzgte Running lean
#17
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looking over the vaccum diagrams, seems I am missing a vaccum controler right before the fuel pressure regulator, also when i remove vaccum before the fuel pressure reg, it runs rich at idle, and lean in boost, so unless someone says otherwise I am going to assume that missing this piece is not helping my fuel problem. i am also seeing some open vaccum hoses elsware not sure where they go, so i am currently going over my diagrams. I am also using the factory sc300 MAF sensor, not sure if that is causing any problems, but according to my diagrams and my research, the supra uses the o2 sensors to controle air fuel, the MAF is pretty much just there to be there. So please lend me your knowledge!
Last edited by 2jzlex; 03-31-08 at 10:39 AM.
#18
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Need to get AFC and add more fuel (tune it on dyno).
I had the similar problem whenever the big boy kicked in 4K.
A/F was all over the place before we tune it with AFC.
WB is also a good idea along with the Fuel pressure gauge.
I had the similar problem whenever the big boy kicked in 4K.
A/F was all over the place before we tune it with AFC.
WB is also a good idea along with the Fuel pressure gauge.
#19
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I have an AEM UEGO (like a part number 30-4100) and I love it. I had an SAFC and it was serviceable and now I have the original MAP ECU1 and it's a lot better.
#20
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Jon
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First off, the car isnt being driven, when i said that under boost it ran lean, it was simply some minor reving of the engine just enough to spool the tubo realy, (Economy Car Service) did most of the work for me while I was at the Nascar Technical Institute in North Carolina. I specialize in BMW and Mercedes, So Im not a total dumb ***, i do have a head on my sholders. there are vaccum lines going to nothing, but they are all plugged. so there is no vaccume leak other than what I purposely unplugged. I was simpy checking to make sure the FPR was working. apparently its either open or closed, there is no happy medium. I am using the 94 usdm ecu. just so you know, I bought a supra 2j,got the aristo motor instead, so as far as im conserned, the aristo motor has caused me a lot of headache. I have gone over all the wiring, and it seems to be all correct.
#22
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First off, the car isnt being driven, when i said that under boost it ran lean, it was simply some minor reving of the engine just enough to spool the tubo realy, (Economy Car Service) did most of the work for me while I was at the Nascar Technical Institute in North Carolina. I specialize in BMW and Mercedes, So Im not a total dumb ***, i do have a head on my sholders.
David
#25
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First off, the car isnt being driven, when i said that under boost it ran lean, it was simply some minor reving of the engine just enough to spool the tubo realy, (Economy Car Service) did most of the work for me while I was at the Nascar Technical Institute in North Carolina. I specialize in BMW and Mercedes, So Im not a total dumb ***, i do have a head on my sholders. there are vaccum lines going to nothing, but they are all plugged. so there is no vaccume leak other than what I purposely unplugged. I was simpy checking to make sure the FPR was working. apparently its either open or closed, there is no happy medium. I am using the 94 usdm ecu. just so you know, I bought a supra 2j,got the aristo motor instead, so as far as im conserned, the aristo motor has caused me a lot of headache. I have gone over all the wiring, and it seems to be all correct.
There are medium points in the FPR, it isn't just open or shut, to make it simple: boost=more fuel at the rail by closing the valve in the FPR, more vaccuum= less pressure and it actually pulls it open to allow more fuel to pass by. Saying all of this, testing this at idle isn't going to tell you much at all. (FYI to tell if an FPR is bad, remove the line and see if fuel comes out the top port) Now what you said you did is remove it and look at narrowband signal that is inaccurate in the first place, and then assumed it was building boost as you indicated in your post. Like Five10H said, revving at idle is kind of irrelevant as you need to place a load on your engine with a wideband to get any kind of real feedback.
If all this seems like I'm being a ****, I am only taking what you have posted word for word and making suggestions and comments. As for the vaccuum lines, they don't go to nothing. If they are there, they are probably relevant somewhere if you are still on stock ecu. Now if you have the aristo motor just remember that that is jdm and the discrepencies between US/JAPAN emissions are night and day.
I think a good thing to do right now is do pressure test. This means you cap off the I/C piping on the outlet of the turbos and hook up an air tank to it then allow roughly 10 psi or so through the whole I/C system, listen for air coming out from couplings, vac lines etc. Once you have done this, open the throttle body and allow the pressure to flow through the intake mani etc and listen for more air leaks. After you have insured everything is good and tight, get yourself a good wideband and go out and datalog your results. It is good to do this with someone so they can tell you when you are leaning out or getting fat and you can concentrate the road and watch what correlating RPM and boost you are at.
Good luck
Jon
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yes, that would be nice, I mean to drive it, but the way it runs it is in no driving condition. the thing hardly runs. while taking a look at the spark plugs, they are a dry black!
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you paying for the hauler...lol
After a quick diagnosis of my spark plugs, it seems that I am not running lean, but predetinating. I tried to check the timing, but it is set and cannot be changed(by the way everything else is in alignment). so why would I be predetinating?(spark plugs have a thick black soot covering the entire end)
After a quick diagnosis of my spark plugs, it seems that I am not running lean, but predetinating. I tried to check the timing, but it is set and cannot be changed(by the way everything else is in alignment). so why would I be predetinating?(spark plugs have a thick black soot covering the entire end)