97 Grand Am High Idle problem and repair people say theres no problem???

Were they able to duplicate the condition? For how long does it idle high?

Quite likely the EGR and/or IAC but you will have to clean the actual parts, not just the connectors. Could also be holes in the air intake tube or dirty throttle body... among others.

IAC, or PCM problems or PCM is mis-responding to bad info from a TPS, or CTS, or anything PY said. You need to find a shop that can use a Scan Tool, not just a code reader. GW

David wrote:

I actually did take both of these off the car and cleaned them and the connectors, but it did not seem to help the problem. What exactly does dirty throttle body mean? I feel like a newbie, haha.

Forgive my stupidity, but what exactly is the difference in a Scan Tool and a code reader? The two places I've carried it to have a fairly large machine and not just a simply a handheld device that read the codes (if that matters?)

As Geoff said, you may need to use a scan tool that will record all settings & codes real time with engine running.

The throttle body tends to collect carbon and junk around, and especially behind, the throttle plate due to a pressure drop. It will sometimes hold the throttle plate open slightly for x amount of time.

Another possibility is dirty (carboned up) Manifold Air Temperature sensor. Could be a hole in the air tube past the MAF sensor, or bad MAP sensor. Could be lots of things... vac leaks, intake manifold, etc, etc.

I forgot to add, with the IAC off the car, hook it up to a 9 volt battery and see if it works ok both directions.

Sorry I didn't elaborate better.... in your statement "I've taken the car to a couple dealers and they tell me that there are no codes showing on the computer so it seems to be fine to them!" I inferred that they don't know what they are doing or do not have fully functional scan tools. Looking for trouble codes is only the first step. Next they need to monitor all the different sensors (with the scan tool) and see if they give any indication os to why the vehicle is doing what it's doing. Maybe the ECT *thinks* the car is sold. Maybe the ECM is *telling* the IAC to move but it won't, maybe the TPS *thinks* your foot is on the pedal, etc... They need to really USE the scan tool not just code check. GW

David wrote:

The problem you stated sounds like one I had. I almost drove it through the fence. I would also shift funny. I had recently had the master cylinder on my 6 cyl., auto, 97 Grand AM SE replaced. I took it to two different trans. shops and they couldn't figure it out. According to the code reader I had a bad Throttle Positioning Sensor.(Buying the code reader @ $120 was cheaper than going to the mechanics to diagnose) My problem was NOT the (TPS). Actually it was the wiring going into the sensor INSIDE the connector. I believe accidently of course that the mechanics working on my brakes broke the wiring where it was not visible. I figured this out after replacing the TPS, and having the same code error and problem after. I found the broken wire by going under the hood and wiggling the wires around the sensor and viola! I took it apart and re-soldered the wires and was good to go. I hope this helps. 50willyman

The problem you stated sounds like one I had. I almost drove it through the fence. I would also shift funny. I had recently had the master cylinder on my 6 cyl., auto, 97 Grand AM SE replaced. I took it to two different trans. shops and they couldn't figure it out. According to the code reader I had a bad Throttle Positioning Sensor.(Buying the code reader @ $120 was cheaper than going to the mechanics to diagnose) My problem was NOT the (TPS). Actually it was the wiring going into the sensor INSIDE the connector. I believe accidently of course that the mechanics working on my brakes broke the wiring where it was not visible. I figured this out after replacing the TPS, and having the same code error and problem after. I found the broken wire by going under the hood and wiggling the wires around the sensor and viola! I took it apart and re-soldered the wires and was good to go. I hope this helps. 50willyman