2001 Cavalier Stalling only when Cold.

I did the following: Replaced fuel filter, cleaned KN Air filter, cleaned throttle body and the little sensor on the elbow... Put Injector cleaner... cleaned other little sensors around and stuff.

The darn thing only stalls when it's cold outside and when coming to a stop. Starts up normal and runs great when warm outside.

I know there are tons of threads on this issue and many of them said about fuel filter which i replaced... Anybody had a specific sensor or part that caused this? No Check engine light and no codes by the way.

Thanks.

Check the ECT and IAT sensors

Where are those 2? Around the throttle body? How do i check them?

IAT is located on the air intake tube, close to the air filter. It's a 2 wire connector.

ECT is located at the water outlet housing or thermostat housing, depending on which engine you have (you should always say in your first post). Also a 2 wire connector.

To test, you can use a DVOM to check resistance, but I couldn't give you the spec because I always use a scan tool (which I'm guessing you don't have). That will also tell you if there is any problem in any part of the circuit because you see what the PCM sees.

If it were an IAT, ECT, or MAP sensor malfunction, wouldn't the onboard computer know and set off a Malfunction Indicator Light on the dash until the problem was fixed and the Diagnostic Trouble Code was cleared from it's memory?

No. If the computer sees 60 degrees when it's 100 degrees out, the computer thinks it's 60 degrees and will give you that much fuel. A code will only set if the PCM is getting no signal. Think of it as you being inside. You look outside through a closed window at a thermometer. If you see 70 degrees and it's actually 20, you're going to walk outside without a coat. Your backup sensor (your nerves) tell you it's not actually 70 degrees and you go back and get your coat. The PCM doesn't have your backup sensor, so it doesn't know there's a problem. If the thermometer falls off the wall, you're going to set a code for "thermometer missing"

I cleaned the IAT sensor then... and i thought it fixed it for a while, then it came back. I'll check the ECT sensor then as well...

Thanks for a great explanation. Awsome post.