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Idle drop and stall at operating temp only. Fuel trim question.

6K views 25 replies 6 participants last post by  quietseas4john 
I fought a idle drop an a very rare stall for maybe a year until I found a discussion like tis here at the nation.
Went to the dealer with a list of PCM updates, one of which was for idle. That morning, with the truck warmed up, it would drop to 400 +/- rpms then settle back to just about 600rpm. When the update was done, I would settle to 675-690 rpm per my Scan Gauge.

Just looked at my work order, this is what the note says for the idle update:

"install available updates for PCM Program Code 1061F"

I'm assuming the PC 1061F was an update name or an address inside the PCM.
 
Part 2 , too quick on the submit button: After the update was installed and the idle was basically stable, never has dropped below 675 that I've seen and it's as smooth as silk.
The updates were done Jan 24 so it's been a couple of months of smooth stops. Can't tell you how many times I searched for a vacuum leak or cleaned the TB, etc etc.
 
OK Guys, am I leaving myself open for a problem?

Over the 10 years I've had the Colorado, I have never cleaned the ground box with anything other than compressed air. Not that I do it all that regularly, enough that I can find it easily tho. cleaned it maybe 3-4 times in the 10 years.
Never brushed the contacts or used Dielectric grease to seal it back up.
Last time I used dielectric grease was on my old 64 Nova for the spark plug boots and to insulate the dual points and condenser. Still got the original tube I bought back in 1974 or 5.
 
Sorry, you are above my skill level.
 
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