2005 Mercury 50ELPT 4S. Fast idle and abrupt acceleration.

[chksix]

I recently purchased this engine. It idles about 1000 -1100rpm. The dealer couldn't slow it down.
When you accelerate from idle the rpm advances to 2500 - 3000 rpm very abruptly no matter how carefully you advance the throttle.
It's very difficult to set a speed between 1000 and 2000 rpm. The engine has only 26 hours on it.
Any ideas?

 

[christg]

whas is the procedure to test idle air control valve ?

 

[racerone]

serial numbers are required.