Banging/thumping sound

[barnesjtsl]

79 2000

After I started the car this afternoon a banging/thumping sound started. Sounds a little like a rod bearing. It accelerates/decelerates with the engine speed.

Don't think it is a rod bearing because it goes away when I push in the clutch.

Any thoughts?

jb

[lm48]

can you record and post the sound?

[131]

If it goes away when you disengage the clutch, it's more than likely a clutch or gearbox problem. Possibly the clutch throwout bearing or gearbox input shaft bearing. Does it make the noise while you're driving, or just when the car is stationary?

[kmead]

It could well be the Guibo which is a flexible coupling in the driveshaft. There is also a drive shaft bearing which can fail in that same area.

Karl

[courtenay]

Have you checked to see if anyone is locked in the trunk?

[kmac33]

Have you checked to see if anyone is locked in the trunk?

Good thought Bruce, but when I lock victims...I mean people....I mean hypothetically, if you locked someone in the trunk, their knocking wouldn't "accelerates/decelerates with the engine". So I doubt this is the cause

Since it disappears when you push in the clutch, I'd also check the flywheel. Could be occurring at the clutch/flywheel interface.

[barnesjtsl]

Luckily the victums I keep in the trunk can't move their arms enough in that confined space to make any kind of sound similar to this.

To confuse the problem even more. After I drove the car for about 2 miles after the sound started it went away and hasn't come back.

Could this just be the beginning of the throwout bearing going out?

jb

[So Cal Mark]

release bearing shouldn't be turning unless the pedal is depressed or the clutch is adjusted without any free-play. If the car has to move to make the noise, I'd look at the flex joint, tranny mount and driveline