Been searching high and low for an answer, and have seen several posts on the net with similar situations, but no answers. I have an 03 Mountaineer, v8 engine, and am having some random stalling issues. Occassionally, at random times (engine coldor warm, outside temp warmor cold, etc), when I come toa stop, the engine starts to rev - RPMs shoot up, then down, then back up then down, car tries to lunge forward, all dash lights go on, and the engine then dies. Starts right back up as if nothing happened, and I can continue on my way. Sometimes if I catch the engine doing it, I can give it a little gas and it will stop and be fine. Sometimes it will happen again a few minutes later, butmost times, it won't happen again for another few days or so. I started having the problem back in early 2006, and it would happen maybe once a month. Since that time, it has started happening more often to where now it is happening several times a week.


Any thoughts or suggestions? Thanks in advance for any help!


Scott

 

Sounds like a sensor may be on its way out. It's pretty unlikely, but
the PCM (I'm a GM guy, and have seen the PCM freak out in rare cases at
a certain RPM) may need to be reflashed...I know they don't "learn"
like GM PCMs...I don't know enough about Ford/Mercury PCMs *shrug*

 

Cleaned out the Idle Control Valve over the weekend. I know the car has "started to stall out" once (in the words of my wife), but didn't go all the way. With a problem like this, it's so hard to get fixed because it's so inconsistent. Could go a week or two without it happening and you think you have it fixed...


Thanks for hte tip Jester - I'll check out the PCM...

 

I bought my 03 Mountaineer used with almost 19000 miles on it. Around 23000 miles it started the itnermittent cutting out and stalling. Service department couldn't find anything wrong, and of course it never did it during the 5 minutes they test drove it. It got to where I was really scared to drive the vehicle because the last time it stalled out was right after I came over the crest of a hill and there were cars right behind me.

I also called the Ford/Mercury 800 number and they were no help, so I figured I was on my own.

I went back through the service records and since I'm a fanatic about following the mfg's recommended service intervals, the only thing I discovered was that the original fuel filter had never been changed and the service manual recommends every 15000 miles. So I had the garage change the fuel filter and the Mountaineer has not cut out on me one time since!!