7mgte shuts off after going past 2500 rpms!!!!

[djsilence813]

So i just replaced my tps,afm and i got 3 iac's "idle air controls" i need to know why when i drive my car and i put it int nuetral after the rpms @ 2500 car dies out please help guys!!!!

Car is a fresh rebuild and it runs perfect when im driving but soon as i GO TO BUILD BOOST THE CHECK ENGINE LIGHT COMES ON AN WHEN I LET OFF THE GAS IT DIES OUT ALSO I GOT A AEM WIDEBAND AND ITS READING PROPERLY SO I "DONT" THINK ITS MY AFM

 

[mkiiichip]

Pull codes dude. And quit yelling.

http://www.cygnusx1.net/Supra/TechTips/engine_error_codes.aspx

 

[D.J.T.]

^ +1
When a CEL appears in ANY car the very first thing you should do is pull the codes..
But it sounds like a boost leak?

 

[IndigoMKII]

Um. Won't go over 2500 rpms and a CEL comes on, I'd say he's either got a code 52 or 34.

 

[D.J.T.]

Um. Won't go over 2500 rpms and a CEL comes on, I'd say he's either got a code 52 or 34.

I doubt its 52. i would hit 4K rpms with 52 on.. & still boost some. Fuel cut would come into place though.

 

[ifyouaint1sturlast]

I had a similar issue and it was my alternator. Alt was dying and wouldn't produce voltage over a certain RPM. Every light on the dash came on and it had very little power. Replaced the alternator and it ran like a champ ever since.

 

[D.J.T.]

I had a similar issue and it was my alternator. Alt was dying and wouldn't produce voltage over a certain RPM. Every light on the dash came on and it had very little power. Replaced the alternator and it ran like a champ ever since.

same here with my MK2.. took apart old alternators from a 90 celica gt & 95 Camry, made a good one with the MK2's & it runs fine now.

 

[IndigoMKII]

I doubt its 52. i would hit 4K rpms with 52 on.. & still boost some. Fuel cut would come into place though.

When I had 52 I had a hard time hitting 3k rpm lol

 

[djsilence813]

thanx and ill pull codes and i have a brand new alternator also.
but you guys done think its iac ?

 

[D.J.T.]

thanx and ill pull codes and i have a brand new alternator also.
but you guys done think its iac ?

This is what I believe "IAC works when the engine is cold. once in operating temp it shouldn't affect idle..." Is this correct?

 

[mkiiichip]

but you guys done think its iac ?

No.

This is what I believe "IAC works when the engine is cold. once in operating temp it shouldn't affect idle..." Is this correct?

Absolutely not correct. Some engines work that way, just not on a supra.

 

[airhead04]

This is what I believe "IAC works when the engine is cold. once in operating temp it shouldn't affect idle..." Is this correct?

Next time the car is at warm idle, pull that hose off and put your finger over the port on the IAC. Let me know what happens. (btw it should make the car die).