Hey i have a 89 supra turbo with a K&N and a cat back exhaust. i did the headgasket 3 months ago and it ran fine but in the past month i have had an idleing problem. I will start it and it will idle then all of a sudden it starts going crazy from 200 to 700 it almost dies then comes back mainly when its hot. It only does it sometimes, It also seems to have a dead spot right when the turbo kicks in. I have had code 52 since i fixed the BHG but could that be the problem???? I plan to fix it soon but haven't had time. It has also thrown the air intake temp code one time but i cleared it and hasn't come back. please help me!! O and it has problems starting too mainly when its hot.
IDLE PROBLEM HELP
- Thread starter supra89t
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Sounds like an air leak. I think I posted something on another thread about checking it. Basically I think you have air coming in and out somewhere where it shouldn't. Like after the afm. Like a split accordian hose, maybe a vacum leak. Possibly you didn't get the intake manifold or throttle body tight or you reused a gasket you shouldn't of. Also your supra is pushing 20 years old and if your using the original vacum lines you may want to consider buying some new hose. I bought the hose techniques kit and it works fine.
All you need to do is get a can of carb and choke cleaner because it is volitale and will cause your engine to change it's pitch. Basically take and spray along the intake manifold gaskets, accordian hose, throttle body, and your vacum lines. Also don't forget about the seats of injectors, the gromets sometimes rip and it squel and you will have a hell of a time tracking it down.
Anyways good luck.
All you need to do is get a can of carb and choke cleaner because it is volitale and will cause your engine to change it's pitch. Basically take and spray along the intake manifold gaskets, accordian hose, throttle body, and your vacum lines. Also don't forget about the seats of injectors, the gromets sometimes rip and it squel and you will have a hell of a time tracking it down.
Anyways good luck.
yeah i have put new vac hoses on it already so don't think thats the problem but i was looking at the fuel injectors and there is a puddle of liquid on top of the manifold but i dont think its gas so idk but thanks!!! i will try the carb cleaner and keep u updated. anyone else have any ideas!!
I think you have a vapor lock problem. You could have a weak pump, pressure regulator that is bad, ECT sensor issues, or even the vacuum switching valve for hot starts.
Read the information in the following link. It is the factory electrical wiring diagram. It explains those inputs and the ECU outputs and how they are controlled. That will help you trouble shoot the problem.
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?Section=Main&Page=044
The reason it won't start hot is the heat soaks into the fuel rail turning it into a vapor before it is injected into the cylinder. Toyota takes measures against that, but it sounds like a component failure to me.
Read the information in the following link. It is the factory electrical wiring diagram. It explains those inputs and the ECU outputs and how they are controlled. That will help you trouble shoot the problem.
http://www.cygnusx1.net/Supra/Library/TEWD/MK3/manual.aspx?Section=Main&Page=044
The reason it won't start hot is the heat soaks into the fuel rail turning it into a vapor before it is injected into the cylinder. Toyota takes measures against that, but it sounds like a component failure to me.
oo that makes since!!! i had 2 replace this thing i don't know what it is called but its on the right side of the fuel rail. what is it???? but anyway i got it off a N/A supra in a junk yard could this be my problem?? thanks for the reply!!!!
ECT sensor problem????? my pwr botton doesn't work and the car shifts at like 4500 all the time can't get it 2 go past that unless i shift it manually. what could this be......
The VSV on the right side is for EGR. The fuel pressure up valve is behind the alternator.
But you have to make sure the ECT sensor is sending the correct signal to the ECU. And make sure the ECU is giving the command to the vacuum valve. And the vacuum valve has to be hooked up to the pressure regulator. And the fuel pump must be delivering enough volume.
Do you have stock sized tires? The shift schedule for the automatic trans is not RPM related, but speed related. If the speed signal is wrong, you will shift early or late. The PWR button does delay the upshift. All that does is switch voltage at the trans ECU to signal the different shifting schedules.
Pull diagnostic codes, I think you will have a few stored for the early shift. But maybe not.
But you have to make sure the ECT sensor is sending the correct signal to the ECU. And make sure the ECU is giving the command to the vacuum valve. And the vacuum valve has to be hooked up to the pressure regulator. And the fuel pump must be delivering enough volume.
Do you have stock sized tires? The shift schedule for the automatic trans is not RPM related, but speed related. If the speed signal is wrong, you will shift early or late. The PWR button does delay the upshift. All that does is switch voltage at the trans ECU to signal the different shifting schedules.
Pull diagnostic codes, I think you will have a few stored for the early shift. But maybe not.
ok thanks! i do have stock tire sizes and the only code i have is 52 ks. i just put a used trans in like a month ago but still shifts early so idk is there any way 2 fix the pwr switch or is that not the problem here. i did the carb cleaner and found a leak on the lower ic hose so that is fixed now just trying 2 get the trans and starting worked out but thanks 4 all the advice.