I have a 97 5.4 4 x 4 - two days ago I left it in my driveway at idle for about 5 minutes - when I came back out the engine had stalled. Took a while to get it started - would turn over but not fire - finally got it started - died 2 or 3 more times on the way to the store - always at idle. Put new gas in it - ran fine the next day - but now today it died on me 3 times on the way to work - always at idle - real difficult to get started back up. This past weekend I put new plugs in it did I screw something up - or is this just coincedence??? When it is running it runs great - no misses etc.

Any advice????

 

Sorry to hear you're having idle problems. Since you're getting spark, maybe your fuel delivery's in question. Maybe a bad fuel filter or clogged injectors? At this point I am speculating of course.

Dan

 

Hey TRW soulds like you've got an IAC (Idle Air Control) problem, all you need to do is go out and buy an IAC solenoid and replace yours it is located on the throttle body and it controls the amount of air the engine receives at decel and idle

Hope this helps

 

[updated:LAST EDITED ON 05-May-02 AT 10:13 PM (EST)]Sounds like the same thing mine was doing a few months ago, and it indeed turned out to be the IAC valve. The part cost about $65 and took about 5 minutes to change out. It might be worth a try for you.

 

>Sounds like the same thing mine was doing a few months ago,
>and it indeed turned out to be the IAC valve. The part cost
>about $65 and took about 5 minutes to change out. It might
>be worth a try for you.





Thanks for the info guys. I replaced my fuel filter last night - going to give it a shot first - if that doesn't do it I'll invest in an IAC valve. I took it to AutoZone and had them run a diagnostic - no codes came up...

 

Hey folks, excuse me I need some room in this boat My 97 Expy would start and then die. I had no problems starting it and keeping it running as long as I kept my foot on the gas. The problem went away for several months and I thought it may have been bad gas. Then the monster reared it's ugly head again. Took it to the shop and turned out to be the IAC. Runs fine now.

 

My '98 Expedition has 90k miles and it stalled at idle about 2 months ago for one day only and again just last week. The Ford dealer diagnostics found nothing. I requested they replace the IAC (per this Forum) and their response they weren't allowed by their protocol if no problem was detected. So with the boldness from this forum, I ordered an IAC for ~$58 and installed it in 10 minutes (maybe could have sprayed gunk remover and cleaned the spring in the solenoid). And this is the 1st work I have ever done under the hood. So give it another 2 months, see what happens - so far so good.

 

My 98 XLT, 54K miles, did this last weekend. Started and ran but dies at idle. I cleaned my IAC with brake parts cleaner and a pipe cleaner. Took a pair of needle-nosed pliers and worked the solenoid shaft in and out a little, put it back on and it's still OK after a week. Still not parking where I have to back up, though.

Interestingly, the Haynes manual had a section for checking the IAC. They said the resistence (ohms) across the two terminals on the IAC should fall into the range of 6 to 13 ohms. My IAC measured at 11 ohms.

'98 XLT 4x4 Expy
'92 Explorer Sport

 

Almost 3 months and no problem with this IAC symptom.

Jim Royalty
98 Tan Expedition XLT

 

IS IT MY IAC OR SECURITY SYSTEM?
Lately, I have noticed that the theft light on my 97 4.6L will flash when I turn the key. When this happens, the car will start and then die. I have to pull the key out and replace it several times, typically 6 or 7, before it will start.

I tried my spare key but the same thing happened.

Any ideas?
Thanks
Keene

 

Keene, your '97 doesn't have the PATS, hence switching keys won't make a difference.

Check your IAC valve.

 

Thanks for the insight Jim. I replaced the IAC valve today and am waiting to see if the starting problem is resolved. I have still noticed the "theft" light flashing a couple of times before turning the engine over. I'll keep you updated though.

However, now JUST LIKE TRW, I thought I'd be a good guy and change the plugs while under the hood. NOW IT'S RUNNING ROUGH. I took it to AutoZone for diagnostics. No codes. I checked the vacuum/PCV valve but the vacuum tube and valve both seem good. WHAT HAVE I DONE?

Keene

 

TRW,
After changing my plugs my '99 started running rough with no computer codes showing. I go so frustrated that I decided to put the old plugs back in. I took out the #4 plug first. You know the one way in the back, under the heater hoses that rips slabs of skin off you hands causing blood to pour into the cylinder well. That one. Anyway, when I took it out, it was wet. I immediately knew that I had screwed up that plug wire. I changed out all the rest, and they were beautiful and dry.

I bought a set lifetime warranty wires for $54 at AZ. Put the new plugs back in, changed the wires and it runs great.

Now I just need to figure out what's wrong with my security system. It's still stalling when the "theft" light flashes with the key turned on.

Keene

 

Another reason for the die at idle phenomenon on a 5.4L is air leaking into the intake between the air flow meter and the throttle body. My wife had this problem in a far away town so it cost her a tow job and a diagnostic at the Ford dealers. The K&N filtercharger assembly had cracked and separated slightly so the airflow meter wasn't getting enough air at idle. It'd crank and die, crank and die. Duct tape solved the problem so she could get home and new silicon rubber sleeves (free from K&N) solved the problem.
Hope this helps.