My car makes a wierd shuddering noise and no mechanic can figure it out?

Question

When the car is warm, in gear, and with foot on brake, there is a slight clanging noise under the hood and the car shudders a bit.

Three mechanic shops later (including the GM dealer) and no one has a clue whats up. New spark plugs and new wires have been tried. They thought it was the flywheel and pulled the tranny. Flywheel is fine. Thought it was the torque converter so changed that. Nothing seems to work.

The car is a 1997 Sunfire and the mechanics are at a loss.

Help!!

Answer 1

They pulled the transmission and changed the torque converter looking for a noise? I think those mechanics were at a loss a long time before you got there. Or they need a new lift for the shop.
Those crooks will no doubt keep taking your money as long as you're giving it away.

Answer 2

Is it a 2.2 engine?, The 2.2 has a history of the timing chain tensioner making a light clanging noise right before it fails and breaks the chain. They also break valve springs which cause a noise and a miss.. Both of these noises are usually there hot or cold. I have seen two cases of an internal transmission part doing what you describe, but not in the transmission of a Sunfire.

Answer 3

Its very possible, that you have a vacuum leak, Check all the vacuum hoses, and lines around the engine area. At idle, you are getting raw air in the system. That could be messing with the PCV valve, its more of a rattling noise. And depending on where its leaking, it may be making the timing erratic ( if possible on that car.), But anyways, Have a mechanic, check the vacuum lines visually. Good Luck!!

Answer 4

Try taking the hand-brake off.

Answer 5

Thats the toob under ur car.

Answer 6

First check for vacuum leaks, then check the motor mounts.