Hi

I have an 97 Bonneville SE with about 116000 miles on it.
I keep having a on and off again problem with the engine racing. I haven't checked the codes for this, but they usually come up for the Throttle Position Sensor. ( I have replaced the throttle postion sensor )

I have noticed that the engine will race when it'* cold and the air cold. The car will run normally after I turn the engine off hot and let it sit for 10 minutes. It'* like I'm driving with the choke on.

Thank You

Could be as simple as your IAT sensor. Intake Air Temp. Scanning for codes will help if there'* any codes there.

Thanks, I'll check that out.

One time I forgot to install the PCV valve when I changed the Upper Intake Manifold and the engine raced like this. I checked out the codes that time and it came up with the Throttle Position Sensor.

I hope to have the chance to check out the codes today.

Might check the PCV valve again and make certain it rattles and nothing is stuck when you give it a good shake. It'* not common for these to go bad, but they are susceptible to getting gunked up on an occasion.

I have one and I just replaced it today, but I still need to go and check out the codes.

Thanks

I know that there is an Intake Air Control Valve on the Throttle Body, but where is the IAT?

The IAT should be on top of the throttle body. There'* 2 sensors there, the one closest to the inlet is the MAF, the other will be the IAT.

The screws are siezed on that part and I hope to get them off to look at it. I do have to confess that some time ago I did spray carb cleaner into the throttle body with the IAT installed.

Carb cleaner down a TB is not good. Especially if you have electronics in the airflow such as MAF and IAT. Get one good MAF/Electrical component cleaner and spray them off, then try again. Let'* see if cleaning will help before repalcements.

Intake Air Temperature sensor is in the TB? Luckily we are all on the same page and are aiming for the Idle Air Control valve.

With a code for the TP sensor though..I'm wondering....what is the actual code number? Many times the PCM sees something and if you have a parts store scan your codes they'll say "oh ...that'* X" and they unforutnately don't know the diagnosis for it. Many of us have the factory service manuals and there are diagnostic tips with each code.

I don't want to see you go buy a part (especially if it'* an expensive one) w/o a good idea that it'* the right part. Watched a guy buy a $160 EGR valve because some folks didn't look up the code. Bored I spent under 5 minutes googling it and asked about his MAP sensor. Oddly enough he had recently used hot glue to hold the MAP together. Sent him a new one and magic.