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Jumping car

when I let off the gas, sometimes (almost always) the car starts to jump. If I press the gas or the brakes, it stops jumping. What is the cause of this? This is on a 94 Beretta with a 2.2L manual tranny

When was the last time the front suspension was inspected? Because from what you describe it may be a lower ball joint that’s ready to fail. And if that happens, you’re in for the ride of your life!

Have the front suspension inspected. I had a 1995 Beretta.

Tester

I don’t know when the last time was. If I can keep an even speed it runs just fine. Is it possible to replace the ball joint without taking it to a shop?

You first have to know how to inspect the front suspension before learning how to replace a ball joint. So no.

Tester

what happens when the lower ball joint fails if Im on the road when it does go?

The tire will fold either under the vehicle or outside the vehicle, and you’ll have no steering.

Tester

Here’s an example of a lower ball joint failure. http://www.aa1car.com/library/wheel_missing.jpg

Tester

" the car starts to jump. "

Perhaps you could elaborate a little more on that…I’ve never seen a car “jump”, except some Mexican creations with hydraulics in them…

the car starts jerking forward (like when a person forgets to shift into neutral when they stop). When it starts jerking, I can either press the brake, gas, or do nothing and it will eventually stop jerking.

I have never seen anything like that.

Clean the MAF, check the operation of the EGR valve, check for a vacuum leak and the throttle position sensor…

where would I find the EGR valve and the throttle position sensor?

Time to by a service manual for your car…

Lol. Thank you. Could it also be the lower ball joint as well? My original thought was that it had something to do with the throttle body itself.

how can u tell if the throttle position sensor is bad