Started as an intermittent problem and is now constant. The engine runs 200-300 rpms higher than before. Idle was 600ish now 950 and at 70 mph it was 2300 and now it's 2600. The tranny shifts when it warms up so I don't think it's trans related. I have scanned it several times with no codes. Its as if the engine doesn't know it's warmed up. Any help would be appreciated.

 

Sounds like your TC is staying unlocked.

 

How would a converter staying unlocked affect the idle speed?

 

I was referring to the higher speeds.

 

That could be, but then there are two problems. Most likely there is one problem causing the engine to run faster than before.

A good thing to check would be to use a scan tool and see if the tach is accurate. I've seen them go bad.