2001 Pontiac Grand Am 4 cyl. Shaking, using alot of gas.

[berr518]

I've had my car for about 2 years now and all the sudden whenever the car is on n idled or every stop sign or stop light it shakes horribly, the whole dashboard and stearing wheel vibrates and anyone in my car can see it. but when i hit the gas to go it stops until i stop at the next stop sign or red light. somebody please help if you know what is causing this... i've been to 4 different garages and none of them can figure it out.

Also around the same time the shaking started my car started being horrible on gas. Its using almost a quarter tank of gas to get from one city to the other when before getting from one city to the other it used way less than almost a quarter tank. I've also had that checked at the garage and they told me there are no leaks or anything, plus about 5 months ago i had a whole new fuel pump assembly put on along with 3 new motor mounts and all these problems started aftwards but the garage that did it keeps saying theres nothing wrong... i know my car and this was not how its supposed to act.

Please help =[

 

[melsg5]

Sounds like they did something wrong when they replaced the motor mounts. Doesnt make sense that 4 shops looked at it and nobody knows whats wrong. Did you tell them this started after the motor mounts were replaced? If you look at the engine when it's running and in gear with parking brake on and wheels blocked is it noticeably shaking? Is your check engine light on?

 

[berr518]

yes i told all 4 of them it was after everything was put on and one of the 4 shops was the one that put the stuff on, and yes its noticeably shaking on and off it likes to stop acting completely weird when i bring it to garages, and no check engine light my friend at one of the garages hooked it up to the machine thing to check and got no codes.