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Discussion Starter #1
Went to start up my 97, 4.6L TBrd today and had some trouble. Car started quickly and immediately stalled when I released the key from ‘Start’ to ‘Key-On’ position (KO). I repeated this with the same result about 3-4 times. Then I applied some gas and tried again. It started and stayed running as long as I had gas applied to keep it going at about 2000 rpm. As soon as I released the gas it stalled out. I repeated that about 3-4 times with the same result. Then I kept it running with gas applied at 2000 rpm for 45 seconds or so before releasing the gas. It then stayed running and all has been fine since then. I drove for 15mins and parked for 2 hours and car started fine with no problems. Took a few short trips and car has started fine with no problems. Didn’t find any codes. Of course, this problem will return so I’d like to get it fixed now before it strands me or someone in my family who will not know what games to play to coax it along. :crying: Any ideas of what is going on or what test to run?? Looking forwards to some guidance.
Thanks
 

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Idle air control valve.

Al
 

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Like T6 said. It's most likely the IAC valve. Unplug the connector to the IAC and try again. If no change in behavior then it's most likely a stuck IAC valve. You can take it off and shoot some MAF/electronics cleaner into the openings to 'wash' it out but that would be a temporary fix if it does anything.
 

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Discussion Starter #4
Thanks for the help folks. I’m sure you’re right about this. I disconnected the IAC and it behaved exactly as it did yesterday before it apparently unstuck itself. It must be intermittent for now. I have a problem with this which is seen in the attached pictures. First pic is just for reference from far away. Note the electrical wire bundle that runs right under the IAC. That bundle is very stiff and doesn’t want to budge. The second pic is a close up that shows the lower IAC mounting bolt butts up against the rigid bundle. To remove the bolt it will protrude into the cable by about ¾ inch before becoming free. The cable won’t like that. I’m not certain what the easiest way to do this is without breaking anything or doing a bunch of unneeded work. Does anyone know the best way to deal with the lower IAC mounting bolt?
Thanks again.
 

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You're like me regarding not wanting to remove extra parts. But it this case, you will have to remove enough to get that cable to move a little.

Stick with a Motorcraft part. Amazon sells a lot of Motorcraft parts. Sometimes you have to get creative to find the part number as Amazon can't always find parts that they sell unless you have the part number first :)

Al
 

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Discussion Starter #6
I did an on-the-car cleanout (probably a little unorthodox). Sprayed a bunch of throttle body cleaner into the IAC valve intake port (hose removed) and let it soak. Then repeated and sprayed compressed air into the same port and repeated that a few times. Then started it and sprayed a squirt until it just about stalled and repeated that a few times. Also verified it stalls as soon as I disconnect the electrical port and starts and idles fine when connected. Then I buttoned it up. It’s idling pretty smoothly now but I can’t say for sure if I accomplished anything. After all, this is intermittent and hasn’t really been a problem since yesterday. I think the only way to replace the IAC is to unscrew the air intake plenum from the manifold and elevate it ¾ inch to get access to the lower IAC mounting bolt. Maybe I’ll give that a try the next time I feel like I need a project. I’m hoping today’s quick-clean will last for a little while.
Thanks for the guidance!
 

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If you remove the plenum, might as well pull it all the way off the car to work on it on a bench, as you should replace that plenum gasket after removing it.

Al
 

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If I recall there is a bracket that mounts to the alternator and intake that can be removed. Once you remove it you can move the harness a bit and the lower bolt is then easier to access. Just jump in with a 1/4" ratchet and extensions; it's pretty easy to be honest.

I posted the same question a year or so ago when I replaced mine. It for some reason looks like a tough job, it's not though.
 

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Discussion Starter #9
Thanks T6Rocket and Kenz. In my case the alternator bracket is a few inches in front of the wire bundle and is not constricting the wire bundle. The bundle runs underneath the left side plenum mounting arm and is blocked by that arm and a vertical mounting post of the intake manifold just about two inches away from the lower screw of the IAC. Seems pretty constrained to me and i can only move it about an eighth inch before fear of cracking it sets in. I don't see anyway of doing it without removing the plenum. Its possible my setup is a little different since I have the Dorman intake manifold, not the original. I'm hoping I bought some time by the on-car cleaning I mentioned. If it acts up again, I'll need to tackle it. Nothing on this car is easy to do.
 
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