Recently I've begun experiencing a problem with my 99 5.4L randomly dieing upon start up. It usually happens the second time it's started for the day but can happen any time. It will appear to start normally then will die, sometimes very slowly. If I start it and gas it to 4000-5000 rpm it will usually catch and run. It runs fine after these episodes but it's becoming more frequent (twice today). I fill it up about every 3 days so I don't think bad gas is an issue. Fuel filter? Any suggestions on where to start looking without getting the dealer involved?

 

Could be the fuel filter,and/or a weak fuel pump? Maybe somone else has had the same trouble,and can help better than I.,,,,,,98

 

Sounds like the Idle Air Control Valve. I first experience the problem around the 50-60,000 mile range. Ford will say it has to be replaced. (about a $60.00 part) I pulled it, cleaned it with carb cleaner and tooth brush and put it back in. Worked great!! Sits up on top of the engine under the firewall on the passenger side. (1999 5.4L, 95,000 miles)

 

Thanks for the responses. Could you be a little more specific as to where this valve is located and what it looks like?

 

About 2 wks ago, i had same problem. I described it as my '98 5.4L wouldn't maintain idle (i had to keep it up at 1k rpm when stationary). Alot of knowledgable and well-meaning opinions reached the consensus of a bad IAC. I was all set to fix it but a MOPAR friend of mine said the first thing that came to his mind was a fuel filter. Had 58k miles on it so it needed replacing anyways. I replaced it (the fuel filter) w/ the intention of immediately going to NAPA and buying the $60 IAC. Well, no problem w/ idle after replacing the filter. Still have the same IAC in and no problem w/ idle since. A very simple and NECESSARY replacement, imho.

 

if you want the locale of the IAC, as well as some advice that it could be the fuel pump (or in my case the fuel filter), go about 4 pgs back in problems/questions to sept 6 or sept 7 to my question "5.4L wont maintain idle". Good luck.

 

Thanks for the info. I found the post you were referring to and it was helpful.

 

Jesus what a pain. I finally got the top bolt out but can't get the bottom one out. Question, can this thing be cleaned without actually removing it? I've made up at least half a dozen new cuss words while trying to perch on top of the engine and cram my hands and tools into a space they were not intended fit into. If I remove the intake hose and spray Carb cleaner directly into the throttle body and expect it to reach the air valve or will that cause other problems?

 

Chilton's (at the top of pg 4-10) says that the IAC is too delicate to clean. Specifically it says in bold type:

"Do not attempt to clean the IAC valve. Carburetor tune-up cleaners or any type of solvent cleaners will damage the internal components of the valve."

If it was me, and I had my heart set on doing this, I think i would either clean what i could with a cotton swab (w/ no solvent) or spend the $60 on a new IAC valve...

 

Mustang88, You are right. A real pain to remove. Breaking the bolts loose initially was the challenge. I went back with some never-sieze on the threads so I won't have the problem next time. Watch you don't drop the bolts or the gasket. Little chance of retrieving them. I did disconnect some of the small plumbing in the area to get my hands in and yes, saw some blood. I realize the book says not to clean but I can't argue with success. Got another 50,000 miles out of it. Now that I realize how common the problem seems to be I will most likely replace the valve next time. By the way, the tapping the valve with a screw driver trick really does work! Spraying lots of carb cleaner in the intake doesn't!! Good Luck.

 

ilb,
Thanks for the info. I was pretty sure the Carb cleaner in the intake wouldn't work or someone would have suggested it, but hey, it doesn't hurt to ask. I hit it with a pair of Channel Locks yesterday and it's worked great since. I guess I'll head to the auto parts store and buy a new one and fight the old one off and try not to lose anything important in the process. I'm already down a Craftsman combo 5/16-3/8 ratcheting box end wrench. I dropped it when the first bolt broke free and although it didn't sound like it fell too far. I can't find it.