car idles, then runs extremely lean and eventually dies

italian89supra · 07-04-2011, 06:50 AM

on my 89 supra turbo 7mgte (cutout exhaust, hks ssqv?

ill warm it up and the idle will jump constantly if i dont give it a little gas

will be fine for a range of 5 minutes and then run extremely lean like high 17s and ---- on wideband

then idle starts to go up and down and eventually dies

im thinking gasket possibly, idk new to turbocharged cars

just recently put in a megan racing aluminum radiator and fixed a short in fan near battery but i dont think that would matter since it doesnt overheat

any help would be greatly appreciated, kinda sucks putting new parts and fixing then something else happens thank you for all your input

Mk3FirstCar-Mike · 07-26-2011, 05:33 AM

If you just got a turbo upgrade and missed upgrading your fuel system with it, that could be contributing to the issue. It could also be leaky gasket somewhere. Clogged injectors might also be adding to the problem (Get GumOut if you think it's the case.) I'll check my manual and get back to you if/when I find anything.

Mk3FirstCar-Mike · 07-26-2011, 05:46 AM

Haynes Repair Manual: 1979 thru 1992 all models.

Engine Stalls:
1: Idle speed incorrect (Chapter 1).
2: Fuel filter clogged and/or water and impurities in the fuel system (Chapter 1).
3: Damaged or wet ignition system wires or components.
4: Emissions system components faulty (Chapter 6).
5: Faulty or incorrectly gapped spark plugs (Chapter 1). Also check the spark plug wires (Chapter 1.)
6: Vacuum leak at the intake manifold or vacuum hoses. Check as described in Section 8.
7: (Skipped in the Haynes manual for some reason).
8: Valve clearances incorrect (Chapter 1).
9: Throttle body bore dirty. With the engine off, remove the intake air duct from the throttle body and open the throttle plate by hand. Clean the bore with carburetor cleaner and a toothbrush (be sure the cleaner is safe for use with catalytic converters and oxygen sensors).

If you figure out what part it is, I MIGHT be able to instruct you on how to fix it, if you need help.

-Mike

Green7mgte · 07-26-2011, 03:45 PM

I bet your check engine light came on when your car was about to die.. if so a code is stored.. run a diagnostic

TOYsORtowed · 07-27-2011, 01:47 PM

If you keep her up around 2000rpm will she stay running? Disconnect the plug running to the black sensor on the air can, your MAF sensor. If the car runs the same and dies still, time to find a new one. I got mine from a friend for $20. $374 new.

07-04-2011, 06:50 AM	#1
italian89supra Stock Join Date: Jan 2011 Location: bakersfield Posts: 16	car idles, then runs extremely lean and eventually dies on my 89 supra turbo 7mgte (cutout exhaust, hks ssqv? ill warm it up and the idle will jump constantly if i dont give it a little gas will be fine for a range of 5 minutes and then run extremely lean like high 17s and ---- on wideband then idle starts to go up and down and eventually dies im thinking gasket possibly, idk new to turbocharged cars just recently put in a megan racing aluminum radiator and fixed a short in fan near battery but i dont think that would matter since it doesnt overheat any help would be greatly appreciated, kinda sucks putting new parts and fixing then something else happens thank you for all your input __________________ HKS SSQV, cutout exhaust

07-26-2011, 03:45 PM	#4
Green7mgte Supra Forum Moderator Join Date: Nov 2009 Location: Green-Ohio Posts: 1,297	I bet your check engine light came on when your car was about to die.. if so a code is stored.. run a diagnostic __________________ 92 Ma71 7mGTE Auto. SafcII Supra FAQ Supra MKIII FAQ Classified Section guidelines :

07-27-2011, 01:47 PM	#5
TOYsORtowed Stock Join Date: Jul 2011 Location: 98270 Posts: 4	Maf If you keep her up around 2000rpm will she stay running? Disconnect the plug running to the black sensor on the air can, your MAF sensor. If the car runs the same and dies still, time to find a new one. I got mine from a friend for $20. $374 new.

07-26-2011, 05:33 AM	#2
Mk3FirstCar-Mike 3" Exhaust Join Date: Jul 2011 Location: Titusville, PA Posts: 54	If you just got a turbo upgrade and missed upgrading your fuel system with it, that could be contributing to the issue. It could also be leaky gasket somewhere. Clogged injectors might also be adding to the problem (Get GumOut if you think it's the case.) I'll check my manual and get back to you if/when I find anything.

07-26-2011, 05:46 AM	#3
Mk3FirstCar-Mike 3" Exhaust Join Date: Jul 2011 Location: Titusville, PA Posts: 54	Haynes Repair Manual: 1979 thru 1992 all models. Engine Stalls: 1: Idle speed incorrect (Chapter 1). 2: Fuel filter clogged and/or water and impurities in the fuel system (Chapter 1). 3: Damaged or wet ignition system wires or components. 4: Emissions system components faulty (Chapter 6). 5: Faulty or incorrectly gapped spark plugs (Chapter 1). Also check the spark plug wires (Chapter 1.) 6: Vacuum leak at the intake manifold or vacuum hoses. Check as described in Section 8. 7: (Skipped in the Haynes manual for some reason). 8: Valve clearances incorrect (Chapter 1). 9: Throttle body bore dirty. With the engine off, remove the intake air duct from the throttle body and open the throttle plate by hand. Clean the bore with carburetor cleaner and a toothbrush (be sure the cleaner is safe for use with catalytic converters and oxygen sensors). If you figure out what part it is, I MIGHT be able to instruct you on how to fix it, if you need help. -Mike