Been having this problem since I got the truck a few yrs ago. It only happens in the winter months. When I first start my truck in the morning, it wants to idle at 2500rpm. It drops down to around 800rpm when its all up to temp. And as long as the engine temp is somewhat warm, idle will stay low. I have replaced tps and cold start injector. Nothing changed and don't want to dump anymore cash into something that won't fix the problem. So here I am, asking if anyone on here has had the same issue and what was the fix? I need to figure this out cuz I'm afraid such high idle on cold engine is just doing more damage to it.

 

Mine will idle up that high when its really cold like -5f to -10f. Then idles down when at operating temp. Seams normal to me. Most of any motor will do that. My diesel trucks would idle up to 1500 to 2000. If it does it all the time even when its say 30-40f then you might have a problem.

 

My truck's cold idle never goes past 1500-1750ish when it's super cold.


Currently with these temperatures in North California in the mornings, it'll idle around 1500 briefly.