Contour Enthusiasts Group Archives Forums General Troubleshooting 2.5L V6 Intermittent stalls upon start

Hi, I could use some help on this one. My 97 V6 Contour GL Sport Auto 84,000 miles has been running great lately when started after I just had the underhood wiring recall done on it at the dealer. And it even idles great upon startup 90% of the time. But the other 10%, upon start, the idle speed goes from 500 to 0 and back a few times and wants to die. It tends to settle down in about 10-20 seconds and then smooth again and normal from then on. If I drive awhile, turn the car off, start it again, it may be fine or may do it again. Days may go by before it acts up again on startup. There does seem to be a loose correlation to filling up the gas tank with the stalling problem. It happened right after a tank fillup within an hour two of the times and several times within a few hours after one. Seems to also want to do it more if the car was sitting a few days without being driven or if driven for some time (hot) and then stopped awhile. It was doing this a few times before the wiring recall work was done, so I don't think/know that it is related to that, but it is much more frequent now. I'm wondering about the fuel vapor system and carbon canister. Could something be wrong with that that could cause occasional odd behavior when it purges the fumes? Don't know anything about this system. I don't seem to have any ordinary idle leaks anywhere because idle is very smooth most of the time, only the occasional startup problem. No codes have appeared or CEL. I did also have the manifolds/IMRC valves cleaned and gaskets replaced while the wiring was being done as well as the cooling fans replaced (one was seized up). Don't think that's related though. Thanks for help in advance.


- Contour_97

97 Contour GL Sport/Auto/2.5L V6/84,500 miles
Love my Contour when it works!

Change the fuel filter and see if it helps. You may have either a failing fuel pump, IAC valve issue or vacuum leak at the UIM gaskets. When it is warmed up, the UIM is expanded and probably stops the leaks.

Duratec maintenance FAQ

Thanks Tony, I had the fuel filter replaced at 60k miles, the IAC at 65 (though didn't seem to make any difference to idle - I found a leaking PCV rubber tube at the exit that was the problem), and the UIM and LIM have both just been cleaned up with brand new gaskets. Idle is SOOO much better (most of the time) than it was before I had that done I can't imagine a leak there. When the idle problem happens, it is very very bad and often will die, when it isn't there it is smooth as silk (close to when this thing was brand new!). I also have both the Ford moose fix pipe and the drilled plug in my car - the combination has worked well for a few years. Could the IAC act weird only 10% of the time? What else could be wrong?

Well, could be but I've had them both for about 2 years. The Ford Moose Pipe Resonator tube fix gets rid of the moose (mostly) but does nothing for the slow rpm change. I did the plug fix to get the rpms to not hang. Also, some times I found when it was really hot out that with just the Ford pipe fix, it would still hum a little at a different speed than before though not as loud. With both in, no moose at all and no hanging rpms either! I had no startup or idle issues for about 8 months or so with this combo, so the system might be more sensitive to idle with both in the system, but I don't think it is root cause. Something else is acting up that is different now than before. Could this be electrical related? I read once about an alternator change for flickering headlights? I don't think I have that problem but it has always been daylight when I've been starting it. I haven't done the alternator mod. Battery is a DieHard about 4 years old now.

I could try taking out the drilled plug and see if it matters - may do that next...