Idling problems after startup when engine has warmed up.

[artorush]

Hello, there is a strange problem I have with the idling when the engine is fired up a right after it is been warm. At cold state the idling is just fine. But as soon the engine goes up to it's usual work temperature, and I make another start up. The idling swings from 2-400 RPM, and the engine tends shuts off, if I don't press the pedal to keep up the RPM.

This state usually stay for about 15-20sec. And it goes back to normal. I have had this problem since I bought the car. There was a period of time when the problem just "disappeared".

Any thought's what this might be? Is there any part's I should investigate?

Thanks for the help.

 

[Failure14]

Well step #1 would be to increase your idle to about 750-800. (Or will it not allow?)
If it is at 200-400 then yea its going to shut off no doubt, not enough revolutions.

So do that, When you turn your car off, do you hear a little click noise from your
engine bay? If not i advise you replace your ISC valve... You can usually get one from the
classifieds here for about $5-$10.
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=106
Here's the TSRM procedure.

And last but not least, check for codes...

If all that doesn't work then we can start worrying about more complicated things.

Get back to us.

 

[YoungGunSupra]

i had the exact same problem..i forgot which part it is aaron from DM told me to replace..i believe it was the CPS..or the TPS..but he said the spring inside it gets old and it causes it to not function properly..just go onto www.driftmotion.com they have the part there...fixed my problem.

 

[artorush]

Can you remember if it was the TPS(Throttle position sensor)? http://mkiiisupra.net/bbs/showthread.php?t=12132&highlight=guide+cam

 

[supraguy@aol]

Failure14- I'm not sure, but I think he was trying to say that his idle fluctuated as much as 200-400rpm. And Young gun was probably referring to the TPS. You can test your TPS, as per the TSRM.

http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=100

 

[Boosted516]

i actually have the same problem, i was going to make a thread about it right now. does anyone know if ge's and gte's have the same iscv? that writeup also says check your throttle, i was having problems with my throttle sticking a few months ago.

 

[jdub]

Well step #1 would be to increase your idle to about 750-800. (Or will it not allow?)
If it is at 200-400 then yea its going to shut off no doubt, not enough revolutions.

So do that, When you turn your car off, do you hear a little click noise from your
engine bay? If not i advise you replace your ISC valve... You can usually get one from the
classifieds here for about $5-$10.
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?Section=FI&P=106
Here's the TSRM procedure.

And last but not least, check for codes...

If all that doesn't work then we can start worrying about more complicated things.

Get back to us.

Excuse me? Care to explain exactly how he can "increase your idle to about 750-800"?

Step #1 - Check for ECU codes.

 

[YoungGunSupra]

yea i meant TPS. i asked aaron about that increasing idle thing too...he said no..was most likely just a bad spring or soething in the TPS..so i got a new one and it fixed the problem..no longer stalls

 

[artorush]

I've finally replaced the tps with a new one. The problem is still there. Any one knows what other thing might be the cause? What about the AFM?

Thanks for your replay.