87 Grand Am SE 3.0 V6 High Idle at start up

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I have an 87 Grand Am SE with the 3.0 V6, I've replaced the TPS, Idle Air Control Valve, MAF sensor and it's been adjusted many times and it still idles around 2000 rpm's when I start it. After you drive it and get it up to operating temperature and restart the car, the idles fine. Any ideas as to what can be causing this? Any help would be great.
 
Have you referred to a manual to see what the cold idle speed is supposed to be?
Is the vehicle new to you?
 
Yes, I just bought it a couple years ago and have had a lot of work done to it.
 
When you start the car it's running in open loop mode, so it uses no feedback from sensors and runs on default look up tables.

Look for vacuum leaks. Also if you can view fuel trims while in closed loop mode if they aren't close to 0 then the computer is compensating for an issue, like a vacuum leak.
 
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