OK, so I am sure this has been covered before, but after searching, I came up empty on my particular issue.

When I start my truck when it is cold out (30's-40's), no matter what the engine temperature is, the truck idles at around 1200RPM's for about 1 minute, then settles down to like 1000 for a minute or two, and then settles in to its normal idle speed of 750 or so after 3-4 mintes. It doesn't matter if the truck is cold or not, it still does it. If the truck is warm, then it takes less time for it to settle in to its normal RPM.

After the truck has been running, idle is fine.

Is this normal?

Thanks for your help.

 

sounds normal to me. mine does it

 

yeah, it happens to me too!

 

excellent, thanks guys. Any idea why it does this?

 

i think to warm up the engine?

 

But it does it when the engine is already warm. At least I am not alone in this.

 

it has to do with warm up. if you want unhook the negative battery cable from the batter for about 10-15 min hook it back up and see if it does it. i bet it will. its normal but doing that will reset the computer.

 

jeez, my truck idles at like 2000 when its a cold start up

 

On this past Saturday it was -20 and my truck idled at 1750 for about 6 minutes before it settled. Sounded like a little diesel. But, it did start up fine.

On task though. Mine idles at 1200 for 30 seconds (almost exactly) every morning. Settles to 900-1000 then only when it is fully warm will it go down to 600 or so.

 

It has to do with warmup and maybe emmissions? So the cats are efficient faster?