Question about my truck = 04 Ram , 5.7

The other day I went to start it to warm up. I let it run about 5 minutes and went out and it would idle high up to 2k for 10 seconds....then would go down to 500 for 10 seconds.....over and over.

A warning light came on and was flashing = ETC (electronic Throttle Control)

I shut it off for a few seconds and it started back up and its ran fine since.

The truck was outside for at least 24 hrs in -5 degree cold. Im assuming thats what caused it ?? It hasnt done it again.

If it happens again, what part do i need to replace or check ?

The Sun. You might want to squirt some carb cleaner in the throttle body to get rid of any grunge.

That and test the battery.If its weak from cold the computer will do ceazy things.Best test is with a carbon pile tester lat actually loads the battery.Most places dont have them anymoe though.Rocky

My 04 diesel runs the idle up when it's below a certain temp. It doesn't fluctuate though. You'll know when the TPS or ETC is going bad. Just keep driving it. Cold wreaks havoc on these things. I would be plugging it in at night if it was outside and I lived where the temp. was that cold.

ok--thanks--hasnt done it since that day