I have a 1994 Mustang GT 5.0 HO stock, automatic transmission.

I just replaced the fuel pump and filter,and got the car driving like it should. Then I parked it for about an hour, had to go somewhere and when I left, it started normally, and went into drive just fine. It was accelerating normally until about 25-35 mph. It won't shift past 2nd. The RPM's just keep getting to about 4500..

I'm so lost please help me...

 

Can you shift it out manually? If so: maybe a vacuum modulator. If not, does it slip?

 

Yes, if I shift it manually, it will shift from 1 to 2, but from 2 to drive, there is no change, and when I press on the gas pedal, it's like I'm in neutral with the RPM's revving to about 5,000.

I was told to check my linkage. But I don't know how to do that.

 

Hmmm... If it was your linkage, it would be hard as hell to even put it in drive. Does it slip in any other gear? I'm afraid you don't wanna hear the diagnosis I'm about to give...

 

It isn't hard to put it into drive, but I was told that the previous owners had trouble with the linkage every so often, and all they did was go under there and mess with it a little, and then it would run good for another six months....

And.... if your going to tell me I need a new transmission, please don't.. The car isn't even worth putting a new transmission into... I just want it to run long enough to sell the p.o.s., and buy a new one... lol

 

Any updates?

 

It could be the vacuum mod is full of water. I've seen that over the years on the early iron models with automatics in them. I can't tell you how mnay time I climbed under there and just disconnected the hose and let the water out. I have no idea how it actually gets in there...just that it does.

On these newer models, it could also be that little piston on the side of the tranny they issued a service bulletin on. I did a little reading on service bulletins on the auto's before I bought my Bullitt and was thinking about buying another car.

Also if you have a handheld computer, see if you can get a code out of it. Since the computer controls shift points it should throw one out immediately. If you don't have a computer, maybe a friend has one?