I've been fighting this for over a year. Only when it gets cold - in the 40's or below. I'll turn the key and nothing happens. All my lights come on, but the car doesn't even try to turn over. Once it warms up, it will start just fine.

It wouldn't start this morning, and I used my load tester to test the battery and it is in good shape. I replaced the Park/Neutral safety switch already, and the starter checks out good as well (tested yesterday - although it was warm then).

I was thinking of putting a new starter solenoid on, but wasn't sure if any of you had run into this before.

I've asked this before and had good information to check, but everything "seems" to check out ok - at least when its warm

 

Oh, its a 2001 Alero with the 3.4 engine

 

Ignition switches are a common problem area in the Alero, but I have never heard of one causing your problem.
What happens when the engine is warm but the outside temp is below 40?
How about if the interior is cold but the engine is warm?
The answers may help you determine the location of the bad component.
I would lean toward an electrical connection not making contact when cold, either in the ignition switch itself or in the underhood fuse block.

 

If I park in my garage at night and start it up in the morning and drive to work (10 miles), I can leave it outside from 7am to 5pm and it will start that evening regardless of how cold the temperature gets outside. AS long as the engine is warm, it will start.

Yesterday it was only in the 50's, and it wouldn't start in the morning (40's) but I went home at lunch, and it fired right up after sitting in the sun.

 

Any security light? That's the biggest ignition switch problem in GMs, it's the wires for the PASSkey system that break just behind the ignition cylinder. possibly try tilting the column when it won't start and see if it has any effect.

 

No,not this time

I've dealt with that problem (and still do occasionally) where I have to turn the key "ON" for 10 minutes then off and then start it.

This problem is just that it won't start when cold.