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Old 01-17-2013, 01:48 PM   #28
pwpanas
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Quote:
Originally Posted by Travis89Turbo View Post
Well I have an update for everyone. Unfortunately this problem is not gone, however i do now have proper compression, and a TT headgasket giving me a more boost friendly compression ratio of 9.2-1.

So... the problem still is it runs rich at start up avg. 12.5+/- It will run in that range for a while approx 5 min. Then drop off carzy lean 17+ at times my AEM AF gauge wont even read it. I have only ran the car for few mins at a time and is not off jack stands so im not going to drive it and do damage with the 17 AFR. The time frame in which it starts to bog and miss (when it falls to anything more the 15 AFR) has gone down drastically from when the problem very first started. Im out of options other then swapping parts. Which luckilty have a friend with a 2jzge in his mk2 that is nice enough to let me use his good parts. Im hoping for a bad MAF

I have a friend coming by the house in a couple hrs to let me try his MAF. If that is not the problem what else would you reccomend swapping to try and troubleshoot??

NEW O2 sensors as well.
1) Thanks for the update - much appreciated!
2) For what it's worth, I wouldn't call 9.2:1 "boost-friendly". Oem 2jz-gte is 8.5:1, and even that is only good for 15psi or so on 93 octane pump gas.
3) Ime, 12.5:1 a/f isn't really all that rich for cold-start. *shrug* However, I agree with you that 17:1 is crazy-lean - I'm guessing that's where your problem is (i.e. not the 12.5:1 on cold-start).
4) If you can obtain some sort of fuel controller to modify the maf signal (eg. APEX'i S-AFC or MAP ECU), you could try richening the fuel curve that way (above idle) - just as a troubleshooting step.
5) Guesses: Test for vacuum leaks. Bad IAC. Dirty injectors. *shrug* - I'll ponder it some more and re-post if I think of anything else. In the meantime, please do keep us updated.

Note: You can pressurize the intake with an air compressor to test for vacuum/boost leaks.
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