99 Cavalier - Cold Star Issues
 

My Cav has had issues in the winter for quite a while, though I don't think it was nearly as bad in 2014 as it was this year.

Once it reaches a certain temperature, I have no choice but to push down on the accelerator when I start it, or else it will stall out. Then I must hold it there until the temperature gauge gets where it needs to be. I've tried circumventing this, it just ends with me stalling out somewhere on the road as soon as I reach a stoplight or stop sign.

Related or at least relevant to this issue is the temperature gauge. I don't know why it does this, but it often fluctuates when I'm driving (from cold to normal and back again, over and over) I do know that I have to hold the accelerator from the point where the gauge starts from cold, and keep holding until it goes up to normal and back to cold again, only then can I let go and drive off.It is at this point that the engine or whatever is warm enough to not stall out.

any dtc set?


the ect sensor is a important input for fuel metering. a shorted sensor would input a false high temperature and an open wiring harness would input a false low temp. this skews the fuel metering and could cause the problems you describe.
start by checking for dtc with a scan tool

I do not know what DTC stands for but I'll see if I can't check the ECT sensor. One of the codes on my check engine light matches that (P0118) so it's likely to be the issue.

diagnostic trouble code


if you only have the p0118 dtc and no others, do this:
-find the ect sensor electrical connector and disconnect it from the sensor
-key on, engine off
-jumper the 2 contacts in the connector together
-if a new dtc sets for ect low p0117, you know the wiring and ecm are ok...replace the sensor. if p0117 does not set either the wiring is open or the pcm is nfg.