I push the gas pedal, and I BARELY touch the gas pedal, the RPM'S jump way up, but takes it sweeeeeet time coming back down to idle. But, it only does it in "P" (park). When idling, the RPM's fluctuate (I'd say about 200-400 rpms, which is a guess, because I don't have a tach). Any ideas? Already tested the throttle position sensor and the Idle Air Control Valve, and cleaned the throttle body. Also, only i

 

Also what?

It will come down kinda slow. Does it make it back down to the proper idle speed? Still the original IAC?

 

I forgot what the "also" was, but no, I replaced the IAC. And cleaned the TB. There is no CEL, but the code reader is showing P0351 (Ignition Coil Primary/Secondary Circuit Malfunction).

 

And yes it takes about 10 to 15 seconds to drop back down.

 

What brand IAC? I know my truck didn't much care for the aftermarket part.....