High Idle Problems HELP PLEASE

[supraguy31]

Ok, Here we go. When I start the car up, the Idle starts out at 1200-1300 rpms and goes down from there once it starts to warm up. It will stop at about 850-900 rpms and once its really warm, for some reason the Idle starts to go back up to 100-1200 rpms.

The only way I can get it back down to the 650-700rpm range is to turn the Screw on the Intake Manifold all the way in. Now, If I drive it for a mile or so, and come to a light, the Idle just Dies and drops to 400. Again, Get out and Adjust the Idle Screw to 650-700 and the just right back up to 1200-1300 rpm.

Can someone Please help me out on this. Its starting to really Frustrate me and I have no clue to what to look for.

Robert

 

[zoonwen]

vaccume leak ???

 

[shaeff]

you're not supposed to touch the idle screw. any adjustment you make, the ECU will just correct. you're chasing your tail there.

check the TPS and ISC.

edit: to add links.

check TPS (throttle position sensor)- http://www.cygnusx1.net/supra/library/TSRM/fi/FI_101.html


Check ISC (idle speed control)-
http://www.cygnusx1.net/supra/library/TSRM/fi/FI_106.html

-shaeff

 

[supraguy31]

Just wanted to say thanks for the Help. I thought about it for a little while and I remembered how bad my Wiring harness was. Went out to the car and what did I find, 4 out of the 6 wires going to the ISC were either connected to the plug by 1 strand of wire of broken off.

So ofcouse, I fixed it so all the wires are connected securely and she Idled great. Thanks for all the help on this Problem.

Robert