I've replaced my IAC and just about everything else in the car and it still idles waaay too low when hot and braking, and sometimes stalls. The SES only came on once in a while. Today I replaced the TPS, finally, and now the SES comes on right away and goes away when I accelerate past half throttle, but comes right back on when I slow down.

Please help, any ideas? Nobody around here can run a diagnostic on it since it's OBD1 and I'm positive it's the TPS. Is there a certain way you're supposed to line it up when you install it?

 

1st I would make sure that base timing is properly set.
2nd: disconnect the AIC and adjust base idle to about 450 rpm. I think that you need to do this in diagnostic mode on the ALDL.
3rd: reset the computer and measure TPS voltage at no throttle, WOT, and make sure that it changes progressively and linearly in between.

 

Timing is right on. How do I adjust the idle?

 

You need to use one of those funny star looking wrenches. I think that it is called a torx wrench, but I don't remember the size. It maybe a T25.
Put a paper clip in the ALDL so that you are bridging the test terminals, don't remember the letter designation on the ALDL for the terminals you have to bridge, but I think it is the two top ones on the right side of the ALDL.
Disconnect the AIC.
Start the engine with the AIC disconnected and with the torx wrench turn the screw on the driver side of the TB until idle is 450 rpm.
Shut off the car.
Disconnect the negative battery terminal for a few minutes to reset the computer.
Reconnect the AIC connector and reconnect your battery. Make sure you remember to remove the paper clip from the ALDL.
Check TPS voltage. If it checks out good, start the car, and it should have a nice and smooth idle.
If the TPS voltage is off, adjust it, or replace the TPS if voltage is jumpy or sticky and does not respond properly as you move the throttle.
Hope this helps.