Scotty,

I have a 2004 Pontiac Vibe with almost 128,000 miles on it, 1.8L Toyota engine, 4 speed automatic. The car runs great! I recently had to replace the A/C compressor but I got one from the junkyard for $26 and slapped it on in no time. However, it revs at about 2,000 rpm when I first start it up, especially when cold, and it holds there for about 5-10 minutes until it slowly goes down to normal. I've cleaned the mass airflow sensor and the throttle body and nothing is different. I've checked a lot of the vacuum hoses and they seem ok (although it's hard to tell). Nothing seems out of place. Do you have any insights as to what it could be? The concern is the toll it'll take on the transmission when putting it into gear at times. Thank you.

Kevin W.