View Full Version : car will not go past 35mph 82 with a 4.1


caddy82deville
09-22-05, 05:21 AM
I need help my car will not go past 35 mph it is a 4.1 in a 82 deville the motor has 91,000 miles on it at a stop sign I have to press on the gas light to take off because if I press hard, it will knock, and really feels like the car has no power so pleas help me out caddy owners Thx. caddy82deville:bomb: :thehand: :mad2: :mad2:

DrDave
09-22-05, 07:09 AM
Try revving it in park. If the idle is reaally rough, there's a good chance it's the catalytic converter. Even if the problem turns out to be something else, the cat is still probably bad--causing hesitation and throttle response problems that these engines aren't supposed to have. They're quite responsive if the cat converter isn't clogged etc. Does the car immediately begin moving with decent power when you tap lightly on the throttle? Or does it rev up a little first before moving? If it revs up a lot before moving, there's a chance the cat is plugged--these stock converters have a tendency to do that.

However, there's also a chance it's low fuel pressure. In that case, you may want to have the fuel pump checked as well (although mine lasted 170,000 miles before I replaced it just to be safe ;-)

Hope that helps!

-Dave

illumina
09-22-05, 03:56 PM
Try revving it in park. If the idle is reaally rough, there's a good chance it's the catalytic converter. Even if the problem turns out to be something else, the cat is still probably bad--causing hesitation and throttle response problems that these engines aren't supposed to have. They're quite responsive if the cat converter isn't clogged etc. Does the car immediately begin moving with decent power when you tap lightly on the throttle? Or does it rev up a little first before moving? If it revs up a lot before moving, there's a chance the cat is plugged--these stock converters have a tendency to do that.

However, there's also a chance it's low fuel pressure. In that case, you may want to have the fuel pump checked as well (although mine lasted 170,000 miles before I replaced it just to be safe ;-)

Hope that helps!

-Dave


Good advice.

Also, if the cat. converter has gone bad, please find out why and correct the problem before you go and replace expensive exhaust hardware. Normally an over-rich fuel condition is the cause of a bad cat. converter. The materials inside the converter tend to clog up from excess fuel being burnt by the very hot exhaust gasses trying to pass through, causing the overheating of the converter.

caddy82deville
09-26-05, 05:07 AM
thanks for the info Ill get it changed