1990 Deville becomes bucking bronco

[dunkindoughbucks]

My beautiful1990 Deville 72,000 miles--had problems on last trip. When I give it gas at 70+ mph it starts bucking like it's running out of gas. If I stop for a while, things cool down and it works great for another half hour on the road. I haven't tried anything--wanted to hear what you folks think. Any ideas?
Thanks
George

[krimson_cardnal]

Pull codes, sticky top of forum page will explain. Get on back with 'em, both history and current. K_C

[carnut]

First guess, FUEL FILTER, second guess, partially plugged cat. converter. pull codes report back

[Tommy Deville]

3rd guess fuel pump on it's wat out.
4th bad plugs & wires

[donwon]

I was haveing that same problem with my 92 Deville.
I think it showed a code for misfire.
The fuel pump was going bad and it kept getting worse
so I changed it and the tank.
No more problems.
Put a fuel pressure gauge on the fuel rail and tape
it to your windshield, when it starts bucking
take a reading of the fuel pressure gauge.

[cadillac_al]

My guess would be EGR system, catalytic convertor, or fuel pump in that order. Good luck.

[dunkindoughbucks]

Originally Posted by donwon

I was haveing that same problem with my 92 Deville.
I think it showed a code for misfire.
The fuel pump was going bad and it kept getting worse
so I changed it and the tank.
No more problems.
Put a fuel pressure gauge on the fuel rail and tape
it to your windshield, when it starts bucking
take a reading of the fuel pressure gauge.

Thanks for your help
George

[dunkindoughbucks]

Originally Posted by Tommy Deville

3rd guess fuel pump on it's wat out.
4th bad plugs & wires

Thanks, Tommy
George

[dunkindoughbucks]

Originally Posted by carnut

First guess, FUEL FILTER, second guess, partially plugged cat. converter. pull codes report back

Thanks for your help, I'll get right on it.
George

[Ranger]

Don't overlook eroded distributor contacts.