ok ive been having huge problems with my car. It was hitting 4200 then just dying, kind of like bouncing off a rev limiter. Had it professionally tuned and all and they could not find whats wrong with it. Well i had the tranny flushed at jiffy lube and found out they put in Mercon and not Mercon V. Immediatley had it flushed at Ford and now it doesn't do that. Now what it does at WOT is rev all the way to 5000 rpm and not shift. However when i take overdrive off and punch it, it pulls and works fine. So basically it seems that when i floor it when in over drive it doesnt shift but without it, it does. What does this sound like?

 

Gotta love Jiffy lube.[:'(]I don't know for sure but it sounds to me like an electronic (tune)problem.

 

Try clearing the computer. Unhook the negative terminal on the battery for about 20 minutes. Not an automatic person myself but it sounds like the tranny is shifting like it's supposed to at those high RPM's. Has it always worked like this for you?

The only thing I can think of is the tranny modulator. Get a new one. The old one may have lost its sensitivity to the throttle and just not kicking the lower gear when you step on it.

 

I guess you are not using a handheld tuner.

Sounds like an electronics problem and not an actual trans issue but I'm sorta retarded when it comes to an auto. [8D]