TPS question

[White00GPGT]

ok so in park my 3.8 loves to rev up and down non stop and when i put it in gear at a stop its all good but if ur on the belt way and doing 65 then let off the gas it kicks up and down all over agian... i was told sounds like a TPS what do u all think???

[Sabrewings]

Or a dirty IAC.

[blueguy]

Movement of the tach could be a CPS too...but I love IAC. Mine went bad during the swap for reasons I ain't saying and...it revs to about 1800 at idle. and sits at about 1200 in D.

[White00GPGT]

well i dont rev high at 1 place it keep going from like 400 to 1300 up and down lol

[Bio248]

sounds like a vacuum leak.

[blueguy]

Check the "T" fittings around the intake manifold...they also attach to the lower intake manifold on the GT's too.