RPM Question

[jwatson21]

My 98 gt is stock except for a cold air intake, bbk catted h pipe and flowmasters. My question is when i rev it up to about 4 or 5 it takes a little long for the rpm's to come back down. any idea's?

 

[Petek]

thats very normal.

 

[GDTrumbo]

Quick drops in RPM tend to expel small amounts of unburnt fuel. The PCM and the IAC valve control this drop to reduce emissions, especially on manual trans cars. Disconnecting the battery for 15 min. and let the PCM recalibrate itself will reset this function and/or the IAC valve/seal can be modified slightly to quicken the RPM drop. I just let mine do its thing.

GT