89 240sx idling problem

[carkook]

I adjusted my cars idle to 750, because when I got it it was a little bit high and the throttle cable was sticking. Ever since I adjusted it, the idle will move around alot, sometimes idleing perfect and then sometimes going to 1500 and sticking. It moves everywhere in between there with the car warmed up and when I first start it. I did some searching and it looks like it could be something with the tps? Im just looking for some advice or help on what to do, thanks

[martins_240sx]

where did you adjust it at...ecu or cable

[carkook]

i adjusted it a small bit by cable, then by the screw on the back of the intake manifold

[MidgetTran]

iono bout the s13, but its practicly the same engine. so iono if this will help you or not. but i had the same problem with mah s14. to adjust my idle, i adjusted the idle adjustment screw behind the engine next to the headers, while adjusting the throttle body at the same time. you dont need to ajust the wire ont the throttle body. but looking at the throttle body from the front of the car. you will see a small block on the right side of the throttle body wit 2 long screws on opposite corners of it. use a 7mm wrench to loosin the scews just enough to where you can rotate the block. (your car should be running while you do this) then you kinda just fiddle with the adjuster and the block on the throttle body. just adjust the screw a little while you rotate the that block on the throttle body counter clockwise or clockwise. and listen to how your engine is idleing or have a buddy watch the tachymeter for you, once you have the rpms where you want it, and its not hopping around. tighten back the 2 screws on the throttle body, (make sure its tight or it'll just loosen back up and your idle will go bad again). then revv up and hold your rpms at 2k for bout a minute to let it save to your ecu. that should do the trick. but like i said, i have a s14. ive never had a good look at a s13 engine before, but im sure both KA's have bout the same setup

[carkook]

I found the problem, coolant temp sensor wasnt all the way down, so it was telling the ecu the motor was cold which would randomly raise the idle to try and warm up an already warm motor.

[MidgetTran]

wownice catch