4.2TDI Engine Noise

[Chaz]

Originally Posted by IT

Definitely sounds off but so hard to pinpoint.

On the second vid it sounds a little delayed, almost like it could be something catching or rubbing on a belt or viscous fan.

And yes, bar a few DPF issues, the 4.2 Tdi is usually pretty bomb proof.....

Thanks.

Is the timing gear on the rear of the engine? The sound does seem to come from the rear but does not pin point to anything directly related to the RPM. It is also random but does increased as the revs increase.

Ill fiddle around over the weekend and see if I can track it down.

Thanks

[snapdragon]

Back of engine..possibly and hopefully vacuum pump.
Just guessing but worth a closer check?

https://www.youtube.com/watch?v=U2PZ4Xklx38
https://www.youtube.com/watch?v=yYlz9pDzfsY

[Chaz]

Originally Posted by snapdragon

Back of engine..possibly and hopefully vacuum pump.
Just guessing but worth a closer check?

https://www.youtube.com/watch?v=U2PZ4Xklx38
https://www.youtube.com/watch?v=yYlz9pDzfsY

Wow, thanks. The Beemer video sounds similar. Ill do some digging about vacuum pumps on the 4.2TDI.

[Chaz]

Originally Posted by snapdragon

Back of engine..possibly and hopefully vacuum pump.
Just guessing but worth a closer check?

https://www.youtube.com/watch?v=U2PZ4Xklx38
https://www.youtube.com/watch?v=yYlz9pDzfsY

I took a quick look. Arent all the 4.2 TDI engine ancillaries around the front of the engine? The sound 'seems' to come from the rear, so not sure.

[snapdragon]

I don't know but on other VAG V-engines, they come off one of the camshafts at the back (on longitudinally mounted engines) The pump is smallish and only one one side and has the air pipes for brakes etc.. coming off.

[Pug]

It seemed to respond more to some sort of pressure. The closest I've ever heard, was a catalytic converter had broken up and made a similar sort of noise. Doesn't really sound like a pulley or tensioner as it would sound more consistent and be in tune with the RPM. These engines are pretty complex so it's going to be either something major, or something minor that's tricky to access.

[Chaz]

Originally Posted by Pug

It seemed to respond more to some sort of pressure. The closest I've ever heard, was a catalytic converter had broken up and made a similar sort of noise. Doesn't really sound like a pulley or tensioner as it would sound more consistent and be in tune with the RPM. These engines are pretty complex so it's going to be either something major, or something minor that's tricky to access.

Thanks.

The only other thing apart from the service was that I filled up with high octane diesel as my local place had run out of normal diesel. If anything, higher octane should be 'cleaner' I would expect.

[Mechcanico Lee]

Wow ! It sounds pretty rough on the second vid , clanky ..... even a bit cranky , doesn't sound like chains to me not consistent sort of slack rattle like chains do
You used a proper oil filter ? Nothing left behind in the oil filter pot from the old filter ?