Originally Posted by bossman302
Ok, sounds like the same issue I had pretty much. Here is what I did to fix my issue.
Back the idle stop screw out till doesn't touch the bell crank arm. Use a 0.010" feeler gauge, tighten until gauge just drags between screw and bell crank arm. Remove feeler gauge. Tighten screw exactly 1 1/2 turns. Start the car and make sure it doesn't stall out.
Next, adjust the TPS so the voltage reads .98 or .99. With the connector attached to the TPS stick a paper clip into the rubber boot on the connector where the middle (+) and bottom (-) wires go into the connector. Set your multimeter to volts. If it is already at .98/.99 you are set. If not loosen the screws and turn the TPS till hit those numbers. If you can't you will need to take the TPS off and enlarge the holes. Make sure the TPS is nice and tight when you are done. Don't want it to move.
Last step. Disconnect the battery and let it site for a little while to reset the computer. Reconnect the battery and start the car but do not touch the gas pedal. Let it idle for about 10 minutes. This will let the car learn it's idle.
After I did this my problem went away. It may not sound like it but this is really easy to do. If you don't want to mess with the throttle that ok but at least check the TPS voltage and reset the computer. I redid my throttle body cause my tuner messed it all up.
OK, the above thread led me into the right direction. I did not have to mess with the TPS so much as reset the idle screw on my TB. Some research reveals that the TPS has a widely variable range for its idle voltage. A Chilton's or Haynes manual tells you that an idle voltage can be anywhere from .5V to 1.0V. Also, that the TPS is NON-ADJUSTABLE. So, that being said, a properly installed TPS can have a idle voltage range from 0.5V-1.0V, at a given specific idle RPM. for example....
car1-idle RPM=800, idle TPS voltage=0.63V
car2-idle RPM=800, idle TPS voltage=0.77V
car3-idle RPM=800, idle TPS voltage=0.98V
All three cars should idle and drive properly, as long as nothing is done to them. The TPS idle voltage vs. RPM is the BASELINE for the fuel/air tables. The computer just needs to know that the voltage input starts at X so it can adjust the table to make it go from X=idle to 5.0V=WOT.
Anyway, whenever any changes are made to the air or fuel system, you modify that air/fuel table a bit. Therefore, when people install CAI, TB, Intake Plenums, Intakes, Injectors, what have you, you are changing values for the computer. The stock table values won't behave properly. However, there is some play that the ECU's stock programming can work with. All you have to do each time is reset the ECU. My recommendation would be that ANYTIME something is installed in the vehicle, the ECU should be reset. That way it can re-learn the new values, and adjust accordingly. This should resolve any issues. If anyone is having issues with hanging revs, or high idle, or minor stumbling, I would try the following steps before purchasing any parts.
1. Check vacuum and intake hoses for damage.
2. Disconnect battery.
2. Clean MAF with the MAF cleaner, DO NOT use carb or brake cleaner.
3. Clean TB and Intake Plenum with carb cleaner.
4. Clean out IAC and EGR valve's with carb cleaner.
5. Adjust throttle body set-screw.
6. Re-connect battery.
7. Start vehicle, and let IDLE for 10 min. Idle should be around 800 RPM. adjust screw accordingly.
8. Idle with A/C on max for about 5 min.
9. Drive vehicle and observe. If there is still a problem, then proceed to troubleshooting EGR and IAC valves.
Hope this helps anybody else dealing with this problem!