Over the few last months or so something strange has been going on with my beloved Expy.

It started out every once in a while when I would start it, it would try to idle at 400-500 rpms, after it idled a few mins it would jump back up to its normal idle speed and everything was grand.

A few weeks later it degraded to when it started, it would idle at 400-500 rpms and I would have to hold the gas pedal down a little for 4-5 mins and it would catch at its normal idle speed..and again..grand.

NOW, its hard to start (must hold down the gas pedal to do so), idles only at 400-500 rpms, but on the highway and normal driving above 15mph its fine.

A CEL kicked on Monday, had it checked and it was P1507 - idle air control under speed

I'm taking it for service tomorrow evening to have:

fuel filter replaced (god knows when/if its been done before)
IAC cleaned/replaced
PVC replaced
routine oil change

Is there anything else I should be on the look out for?

I'm trying to avoid being bent over again on this truck. My starter solenoid went out a week after I bought it used (didn't know that was a known problem at the time), and first said it was the battery and sent it home with me...next morning wouldn't start, so they replaced the entire starter along with that nice expensive starter cable

Thanks in advance and I have to say this forum has been a great asset in trying to track this issue down.

 

I had the same problem, I tried to clean the IAC, and that did not work, so I replaced it.. Starts, runs great now. Save yourself some $ and do it yourself..
While your there, replace PVC and look at the vacumm line that goes from the back of the throttle body to the brake booster.

 

Granted I'm about as mechanically inclined as a 5 year old girl, I did learn to work on my accord myself (I had the only lemon accord in the world, and repairs were a fortune). I did want to do this one myself since the part was so cheap, but my apartment complex is strict about working on cars in the lot. Since I'm new to the area, I don't know anyone with a garage yet.

Thanks for the info nojeffgordon.

 

no problem.. To do it, you need an 8MM wrench / socket, 1/4 drive. The part is way back under the firewall. I took a large blanket (dont tell the wife) and layed it across the core support so that I was lying across. You lossen the bolts (be careful not to drop the bolts like I did,) release the elect. tab.
There is a gasket between the the valve and mount.
I tried to clean mine and it did not help, so I got a new one at auto zone for $34.00 (Ford wanted $80.00 for the part).
Ford wanted $212.00 to do what I did, so I was proud that I did it.
Good luck..

 

My wife's Expedition started stalling at low speeds yesterday - our first real cold snap is here as well. After reading the posts it became apparent that the IAC needed replacing. $39.99 later the truck is running like new. Just as I was finishing tightening the last 8mm bolt on the IAC my butter fingers dropped the ratcheting wrench into the engine valley. I can't see it nor can I get a telescoping magnet to contact anything. Any ideas on how to retreive the wrench without taking the top of the engine?

 

I guess a mirror and a magnet? I lost one of the 8mm bolts when I did mine and Never found it. I sure did not have a 8mm bolt laying the house, another trip to the auto parts.....

 

Gentlemen, that is exactly why i decided not to replace mine myself. My big `ol meat popsicles would've caused me to drop something behind the engine.

My expy is back to running normal. So I can now go back to sitting on the beltway and not having to worry about it stalling.

The ppl at firestone said my check engine light came back on, and gave a speed sensor code after they cleared the p1507. They claimed they didn't clear it, so it would be reminder, but I've yet to see the CEL come back on and its been 2 days of constant driving.

Again thanks for all of your advice nojeffgordon.