My '98 Expy 5.4 will turn over without a problem, but unless I keep my foot on the throttle, the vehicle stalls. It doesn't cough and die, the rpm's just quickly and steadily dop to 0 and the engine turns off. If I give it gas while sitting in park, everything sounds normal throught the rpm band.

Any ideas on what to look for?

 

HMMMM, I'd say the IAC valve is shot....very common and easy to fix. Part is around $70 and located on the backside of the throttle body. Try a search of "IAC valve" and you'll no doubt find tons of info.

 

Hey Jim - we should make you assistant moderator

Between you, Tyger25 and Rtpjunior, I can just sit back and let you guys handle it all

Jakermc - click the link in my sig and put "EOG" in the subject line of the email. You'll get all directions you need for replacing the IAC.

XXL

 

Thanks for the quick responses! I've got the EOG now and you've saved another newbie from a needless expense ....

 

Naw, you're doing such a superb job as el jefe, I don't think you need any help.

I do enjoy helping people though. I found this site four years ago when I began rebuilding/restoring my '68 F250. Without the help of everybody in the '67 to '72 forum, I'd never have gotten the beast rolling again, so I feel compelled to help others....without too much commitment.

 

My wife just called me and her 98 Eddie Bauer is doing the same thing. I just registered on this site so I could get the EOG, but the site wouldn't let me (newbie). Can anyone email it to me? Any way to tell if the IAC is shot or if a cleaning would do the trick?
Thanks, Luke

 

Usually a cleaning will revive an IAC for awhile, but replacement will buy you about 50k miles of insurance. If you get a new one, be certain to get the mounting gasket. Ford does not package this with a new IAC (cheap, aren't they?) but it is available under a different part number. If you clean it, you must use throttle body cleaner (not carb cleaner!) that is safe for oxygen sensors (should declare such on label).

 

Well, thanks to this board, I just changed the IAC valve on my 99 expedition with the 5.4 and cured the intermittent idle problems I was having. I needed the part ASAP so the local dealer nailed me for $85.02 + tax. At least the parts guy threw in a free gasket after I "forgot" to ask for one until after the invoice was printed. I agree with the posts that say this a simple repair but add an extra 10 minutes to the job for fishing out the 10 mm socket with a magnet after you drop into the black void beneath the intake. Now that I know the Ford part number ( YL3Z-9F715-AA ) I see that I could have gotten the IAC valve for $58 from http://www.fordpartsonline.com/
Thanks for all the help everyone!
Jeff

 

I need to replace my IAC valve on my 5.4 '97 Expy...and as a newbie can't e-mail for directions...

Any help would be appreciated.

 

Where is BigMattXXL?

 

Just do a site search on "IAC replacement". You'll find all the info needed.

 

HI, I also have a 1998 Eddie Bauer Expedition. Before you start replacing parts you might want to check the Theft system first. WHen you start the truck you will see a light that reads "THEFT" illuminate by the RPM gauge, if it stays solid the truck will start and run with out a problem. If that light is flashing, the truck will start and IMMIDEATELY shut off.

THE reason this happens is, when you park the truck out side in teh sun and the dash heats up enough, it triggers the theft system for some un-known reason. For actually issued a TSB for this problem.

You can get it to start sometimes, if you flip the key around. It sometimes takes me 15 tries to get it to start. I recently installed a remote start on the truck and that took care of the problem. Now i just start it with the remote.

Hope this helps./

 

I have a 99 expo. I was having a really bad hesitation and had it checked out and it was the MAF that was my problem. SO the next day i go out to get the part to the truck and start it up, and it shuts off, had to do it about 5 or 6 times before i realized that i had to keep my foot on the gas fo a bit. But once i repaced the MAF sensor the truck seemed to run fine, now I am still noticing the problem again, but its not as bad, could it be my IAC

 

Could someone email me the EOG. Thanks!

 

My truck was one of the ones that would start but would not stay running without my foot on the gas. Just to let you know, yes, it starts off as a once in a while thing but sooner or later, if it's the IAC valve you'll be driving to the parts place with one foot on the gas and one on the brake!

As a follow-up to my plea, which I did not get an answer to (the guy who has the instructions no longer posts here evidently) I will let tell you that it was the IAC valve. But I tried to clean it and put it back in. Didn't work. Ended up at the machanic. He hit it, gently I guess, with a hammer. That is the test. It started right up so he replaced the valve.

My expy is a '97. I went to the parts store and bought the book for about $16. It's starting to come in really handy. The directions aren't great but the pictures help to identify what I'm looking for.

Good luck.