What makes a car shake when put into DRIVE?

[Mark B]

Hey guys,
I just finished a head gasket fix on my beater car. Its a 1993 Cavalier 2.2L/Auto. Anyway, I got it running today! However, I am running into another problem. When the car is idleing in park its fine, but as soon as I put the car in drive with the brake on, the car shakes! I have expierenced this before, but I never found out why it does this. Any thoughts?


Thanks in Advance,
Mark B

[Christopherrr]

correct me if I'm wrong...but all autos do this.

Automatics are linked from engine to transmission via fluid. Now, when it's in neutral or parked it's not linked, or disengaged. When in drive, it's engaged...so even if you press the brakes, you're still engaged...that's why your car moves forward when you release the brakes in drive.

Why it shakes, beats me...I think it deals with the bushing and mounts that your transmission and engine are on.

[Mirroredshades]

Is the idle set too low? Running too lean? Clogged air or fuel filter? How about a broken engine damper/brace?

[TODD 2000 V6 CAMARO]

I think I might have an idea as to why your Cavalier is shaking on start-up. It might have something to do with where it is sitting when you are starting it. For instance, is it, by chance, sitting next to your T/A when you start it? Being next to one of those cars can tend to strike fear into the heart of lesser cars, so a tremble or two is to be expected. I hope this helps a little. You might try covering the T/A or parking it in the garage so the cavalier won't be able to see it. Just my $0.02.

[~~L-Tree-1~~]

LOL!!!!!!!

[Mirroredshades]

Yeah, my car shakes when I put it in gear too. But mine is from the HORSEPOWER!

[dochidalgo]

Time to replace...

..the torque converter....Check the engine/trans mounts too.
I've heard this problem a lot with the local GM dealer mechanics.
Take care and good luck
Doc

[Rob B (shoebox)]

Inline 4 cyl engines are inherently rough, too. If it smoothes out when you give it a little gas, it may be nothing.

[Joe 1320]

Sounds like the IAC. The TB never actually completely seats, and a certain amount of air gets past the blades. The IAC solenoid is responsible for metering additional air according to fuel used, into the intake to regulate the idle speed and quality. you might want to remove the IAC, clean and re-install.

[Mark B]

Thanks for the replys everyone.... I will check all of those things.