This morning when I got to work and parked my truck it stalled when i put the gear selector in park. Any ideas? I've seen a couple of posts that blame this on a bad IAC is there a way to confirm this is the case before replacing it?

Also, I put a K&N FIPK cold air intake on a little over a week ago. I've checked it for air leaks and it's on there good and tight. Could this have something to do with it?

Truck is a 2004 Fx4 II 4.0L auto.

 

Before you go and replace it try cleaning th IAC first. Also clean the throttle body, MAF, and check the 90° hose to the PCV for cracks or leaks.

 

x2

I had the same problem. I also replaced plugs/wires and fuel filter. Not sure which one fixed it but it's fixed.

 

seems like everyone is cleaning IAC today...me included.

 

Will do. Picked up some contact cleaner on the way to work today. Will that work for the MAF as well as the IAC?

Plugs and wires were done a couple of months ago. I'll give the fuel filter a shot after I try the MAF and IAC.

 

Yes, what did you purchase? CRC air intake cleaner is awesome stuff. Itll do TB, IAC, and MAF without any harm.

Be careful with the MAF though!

 

Picked up a generic electrical contact cleaner (Motomaster) from Canadian Tire. Made sure that it won't leave any residue or film as I was told I should avoid those. They also had MAF cleaner, but I was pretty sure that the contact cleaner would work for both IAC and MAF.

 

Any electronics cleaner will work. I used the same MAF cleaner on my MAF, IACV, and Throttle body.

 

Truck's been running fine for the past week although I've noticed in the past couple of days that it seems to be idling higher than normal (around 1000rpm instead of 6-700rpm). Seems to run fine, and doesn't stall in park anymore. Is this change in idle speed something I should be concerned about?

 

Mine runs anywhere from 700-1200 at start up, after warmup it should drop to 500-800 for sure. 1000 seems high. Is it constant?

 

I cleaned it again and everything seems to be normal again. Maybe the IAC is on it's way out. I'll keep an eye on it for a while.

It was idling around 1500 right after start up and then dropping to around 1000.

 

what does IAC stand for?

 

nevermind i figured it out