'84 GT wont go over 65mph?

[98SteedaStang]

Hi everyone! I've been having a problem with my '84 GT. Its a 20th anniversary with the CFI fuel injection system and an AOD trans. It only has 48,000 miles on it. The problem is when I get around 60-65 mph the car starts bucking back and forth and I cant go any faster. The RPMs tend to stay at about 2000. The more I press the gas the worse the bucking gets and it don't seem to go any faster and the RPMs don't seem to raise that much. Usually when the bucking starts I just let off the gas, I'm too afraid to push it. Any thoughts on what this could be? Is this a trans problem or a rear end problem? It doesnt seem like its coming from the engine.
OK, thanks for your help!

 

[Mustang5L5]

Is it doing this in both D and OD?? Also the problem that the car doesn't want to go over 2000RPM or that the car doesn't want to go faster than 65MPH no matter if the trans is in OD or D?

 

[90mustangGT]

How does it accelerate? Does it get to 60-65mph good but then stop? If so then I would suspect some type of speed limiting divise going whacked.

 

[98SteedaStang]

How does it accelerate? Does it get to 60-65mph good but then stop? If so then I would suspect some type of speed limiting divise going whacked.

You think they have that on an '84?

 

[98SteedaStang]

Is it doing this in both D and OD?? Also the problem that the car doesn't want to go over 2000RPM or that the car doesn't want to go faster than 65MPH no matter if the trans is in OD or D?

Yeah it happens in drive and overdrive.

 

[jerry beach]

How does it accelerate? Does it get to 60-65mph good but then stop? If so then I would suspect some type of speed limiting divise going whacked.

Answer this question too, cant guess without knowing.

 

[90mustangGT]

The first computer controlled cars came out in '83, and there were goveners put in cars as far back as the '70's. As we all know, the goverment became real "speed consious" because they dropped the maximum speed of any road to 55mph and made the maximum a spedo could read as 85mph.

Once again, how does it accelerate and rev below 65mph?

 

[dastang2]

you think it could be something to do with spark. or maybe a clogged fuel or air filter

 

[Icepick]

Something else to think about is the fuel filter may be clogged.