Hey guys...just got the 9er home, and stopped to get the mail. I noticed that when in park, the engine was surging from normal idle position of around 750 RPMs down to 250. It just keeps going up and down within that range. I then put it in Drive...and it dropped even lower, and still surged, and almost cut out.
I have a new IAC and a new TPS, as well as a new coil, cap, rotor, and wires.
I just replaced the plenum gasket over memorial day.
Any idea's what I should check? This is the 1st time this has happened. I did look for a vacuum leak, but heard and saw nothing.
Thanks for the help!