stakes

Engine is knocking at cold start, starting when the car is warm, or when I go from reverse into idle.

Engine knocks for about 5-10 seconds until I press on the gas. It actually sounds like something is vibrating underneath the car, but when I opened up my hood, it was clearly coming from the engine block.

Recently had my timing belt, tensioner and all valves replaced.

Mechanic said it might be the hydraulic pump that releases oil. Not sure. Any ideas?

A4SilverT

Why?

Did your timing belt break and the engine seize, i.e. the valves interacted with the pistons up-close and personal? If so, a new engine is usually needed.

Several things to check. First, get the car VAGed to make sure it isn't a real knock. VAG codes will tell you.

Did this problem start when you had the timing belt replaced?

Search the archives for "cam chain tensioner." That produces a banging-like sound at idle at the rear of the engine.

stakes

Yes, timing belt broke doing 60 and the engine seized. Luckiy that the valves didn't hit the pistons, but all valves were bent and had to be replaced.

Engine noise started before the timing belt decided to go.

Will speak to my mechanic about getting the "VAGed" and will check the archives for cam chain tensioner.

Any other thoughts? Could it be the hydraulic pump that distributes oil like my mechanic mentioned?

Thanks VERY much for your help!

A4SilverT

I think you were hosed, but I'm over my head here. I'll try to steer some of the real experts in the direction of this post.

qfrog Ti20

interference as in what happens when a valve is in the path of a piston with the engine out of time... in other words... pistons smash valves when your timing belt gets loose or breaks or the engine is out of time.

A4SilverT

Since the knock started before the timing belt went, they would seem to be unrelated.

I've never seen a post describing an oil pump failure where a knocking was described.

What's the effect on the pistons of the collision with the valves? And what about the head from bent valves? Why is this car still running?

Kris Hansen

at idle? Sounds very much like a weak oil pump, i'd get it replaced ASAP, especially considering the sludge issues these engines have to deal with.

83UR-Dont-run

Sounds like cam tensioner in back of motor, if not your screwed