[jmcconne]

Engine starts and runs well. After being parked @ 8-10 hours engine starts. RPMs are under 1000 but then go down and engine stalls out. The engine light does not come on. Any info as to cause. One mechanic told me if the engine light doesn't come on, the problem cannot be diagnosed because there will be no error code.

[Casper98GT]

One mechanic told me if the engine light doesn't come on, the problem cannot be diagnosed because there will be no error code

Maybe someone should ask him what he would do when a broken valve spring cause a misfire ? Thats the dumbest thing i have ever heard.

So he is saying only time youre car is broken is when youre CEL is on... hahaha. yikes.

So.... here is what i would try. find youre IAC on youre car and when you start it. give it a tap of a wrench or a hammer. might come out of it.

[03 R Code]

Yeah I've heard that about the idle air control valve a lot. Can't you just take those apart and clean them out without having to replace them?

[Drgnracin72]

yes. its pretty simple. just some carb cleaner and a q-tip wll do the trick

[lemon]

Originally Posted by drgnracin72 yes. its pretty simple. just some carb cleaner and a q-tip wll do the trick

pansy. :wink

grab some carb cleaner, a rag, a flathead screwdriver, and the tools to get the iac off ( 8mm or 5/16 socket plus a ratchet ). pry off the electrical connections to the iac valve ( located right on the front of the plenum ( and has a hose attached to the inlet tube ) , and then remove the 2 bolts, careful - there is a gasket - if its in good condition, it is reusable )...

to clean - spray in the iac valve. liberal amounts are ok, but there are multiple sprays, so keep that in mind. shake out the excess carb cleaner. spray again. wrap the screwdriver head up good to where it wont scratch the insides, and swipe around in there. spray again. empty excess liquid. spray and leave in, smoke a cig, drink a beer, or something that would take about 10 minutes. return, spray again, use the rag and screwdriver again, spray again, empty excess fluids. spray again, let dry.

remembering the gasket, put back on the plenum. install bolts, reconnect air supply hose. start her up, rev a few times, let it idle inbetween revs... turn off, start engine, rev again, let idle for a bit. should be good. if not, repeat all over again.

[Casper98GT]

I can picture steven sittting at his desk with a q-tip going to town.

[Drgnracin72]

haha thanx. i didnt even think expliang how to do it!

[Casper98GT]

its ok, it was just funny thinking about it

[gills99stang]

that was a hell of a procedure... i should counted how many times you said to spray it. but it sounds like the exact same way that i would describe it. better to extra clean, than to not do it enough and put it all back together, only to pull it out again.


I had the SAME exact thing happen to my '98 Mark VIII LSC... would start it up after sitting, RPM's would go down, and it would die. It would even happen at a stoplight sometimes, and was really annoying. I turned it in to the dealership, because I needed some fancy electrical work checked out anyway, and they went ahead and replaced the idle air control valve for me.

[raceruler03]

yeah I had that problem with mine a year or so ago. Our cars have a bad problem with it getting stopped up.