New to the forum. Got a 2001 4.6 GT 5 speed. Starts and runs well but is slow at engine returning to reduced rpms during up shifting. Returns fine when I unplug the idle speed motor so don't think a vacumn leak is an issue. Replaced the idle speed control and the problem remains. The TPS seems fine . It is not throwing any codes.

Any other things I need to check that might be sending some signal that makes the motor slow in reducing rpms??

Any help would be appreciated.

Thanks, Jack.

 

Idle air control?