My 89 TII idles at about 2400-2800rpm for about the first 15 minutes of driving. The power feels like it's down atleast 25% during that time. After that it idles pretty solid at about 700-800 and pulls quite nicely. There are no mods done to the car except cat-back and a stock replacement radiator. The car has low compression 60-60-85 and 85-85-85, but since it eventually gets to a decent idle I don't think that should be the problem.

I really don't know where to start on this one. Most of the idle problems I find when I search are when the car is fully warmed they have problems. I understand it should take a while for the RPM's to drop, but i thought it is supposed to be a slow progression. At some point the car just decides to drop it to 800 instead of 2500, the slow down takes about 3 seconds from high to low. Any help is apreciated.

 

well idling high on cold start is pretty normal, and the reason while you might not feel like your car is pulling hard is because the engine is running really rich durring warm up proccess which kills your power. Also you should stay out of boost durring warm up, and you shouldnt't rev past 3k.

 

after cruising for 10mins on the freeway, the car should not still be warming up.

 

I know my car takes about 10 to 15 min. before it hits operating temperature. This is while going about 50-55 mph.