All possible causes for engine to lean out

[silvergsx623]

I need some ideas of all possible causes/problems that would cause your engine to run lean off of idle.
When i free rev, from idle, the engine stumbls (runs lean) and the rpms drop. I can't get it to rev any higher than 1100 rpm.

The idle is perfect, as smooth as it has ever been. Fresh plugs about 3 weeks ago.

Thanks guys!

 

[suprahero]

vacuum leak. not enough fuel (of course)

Have you checked for codes? Have you recently installed a lexus afm with stock injectors?

What part of Alabama are you from?

 

[suprahero]

OOOPS, I see you have a 2jz.........so I guess you don't have a MAF.

 

[silvergsx623]

I'm using 7mgte stock electroincs to run the 2jz, except for the idle speed control valve and the tps. Everything else is 7m.

I am only getting 1 code, which could be the problem, but I'm wanting to make a list of things for me to check.

(im from the anniston/oxford area) I saw your supra at the last steele supra meet i went to, Jay ? isn't it.

 

[silvergsx623]

would a shot afm cause it to stall like that? I figured i would be able to get it to rev up some, even if the afm failed.

 

[tbcmorris]

When my afm went it acted very similar to this, great idle stumble off idle and not capable of reving past like 2800rpms. GL

 

[silvergsx623]

I'll add the AFM to the list.

Thanks guys, keep the ideas coming

 

[Supracentral]

MAF, TPS, VAC Leak, Defective FPR, Short in wiring harness.

You're using 7M electronics, how do you have your TPS & ISC wired?

 

[silvergsx623]

Thanks Mike!

I will add those to my list.

I will have to find the link. I got the wiring directions from here on the board for both the isc and tps. They have been working perfectly sense june 2008.

I'll find the link and post it up.

Again, Thanks for all the ideas guys!
Hopefully tomorrow i'll be able to troubleshoot.

 

[silvergsx623]

ISC - extend wires, use 2JZGE ISC - There's no way the stock wires will reach the ISC as it is way over on teh exhaust side of the head, I just extended the wires, the plugs are the same on both cars, I didn't check the wiring, but I assue it's the same.


For the 2jz TPS wiring
Ground: Brn/Blk(2j) to Brn(7M)
Idle Sw: Red(2j) to yel/blue (7M)
BCC: Blue/Red to Blue/Red
Signal: Yellow(2j) to Wht/Red(7M)
http://www.supramania.com/forums/showpost.php?p=1017927&postcount=194

again, Thank you guys for all the help!

 

[suprahero]

Yeah my name is Jay and I was at the last supra meet in Steele. You should have introduced yourself. Contrary to popular belief, I'm a nice guy. Hope to see you around.

 

[silvergsx623]

Yeah, i'll introduce myself next supra meet. :icon_surp

Also... Problem ended up being my Apexi SAFC2. Apparently it died... was not sending any voltage out for the ecu to read. So i just disconnected it and the supra is back running.:biglaugh::biglaugh:

Thanks for all the help guys!

 

[dok33]

Sorry, missed this thread. Had the same symptoms at one point, ended up being my SAFC as well. Somehow lost its memory and the AFM type.

How's the car running? Don't remember seein any updates to your build thread after you got it runnin...

 

[silvergsx623]

Sorry, missed this thread. Had the same symptoms at one point, ended up being my SAFC as well. Somehow lost its memory and the AFM type.

How's the car running? Don't remember seein any updates to your build thread after you got it runnin...

Hey man,

Yeah, sense the motor swap its been running better than it ever has. Its had a few issues... braking the rear sub frame:naughty::naughty::biglaugh:, hot start problem, (i believe its the starter) and this problem with the afc... nothing to do with the engine though.

It has started missing under boost... when i get up about 4k rpm under full boost, it sounds like i have an anti-lag set up on it, lol

Other than that, its been running great

how is yours doing?

 

[dok33]

Nice, glad it's running good for ya! Sounds like you've got some ignition breakup, check your coils, cps, plug wires etc. What you have your plug gap set at? Had to gap mine at .022" to prevent breakup.

Mine's running really good, 15psi is a blast! I'm in the process of dropping some 880cc injectors in so I can run more