Rattle/ tapping noise when idle.

[jcp]

Hi, I have a loud rattle/ tapping noise when the engine is idle - any ideas what this could be?

 

[quattrojames]

Need a bit more info.

Diesel or petrol?

What kind of tapping?

Where in the engine is it coming from?

Is it engine speed dependant?

Does it do it all the time?

etc etc

 

[jcp]

It's a petrol 1.8T. The sound seems to be coming from towards the back of the engine.

The tapping is not always there - and seems to go away when the revs raise above 1000 rpm.

Thanks in advance.

 

[jcp]

Just a quick update - audi have suggested that it could be the cam chain tensioner, however they are not sure why the noise is only there on start-up and when the engine has reached 90c.

Any ideas.

Thanks

 

[Broken Byzan]

It is common for the cam chain tensioner to give problems. It is exasperated when warm due to lower oil pressure and thin oil, and at start up due to the oil having drained away from the tensioner itself.

You may also find that your oil pressure itself is a bit on the low side due to partial sludging/blocked strainer.

How often do you change the oil, and using what type of oil, also has it ever been flushed fully?

 

[jcp]

The oil is changed every 20k by audi 5/30 I guess. Do you suggest that I flush the engine before getting the tensioner changed. If so what the best way to do it?

Thanks

 

[J7USS]

Have you had your CAT checked????

 

[jdp1962]

The oil is changed every 20k by audi 5/30 I guess. Do you suggest that I flush the engine before getting the tensioner changed. If so what the best way to do it?

Thanks

I'm not a fan of 20,000 mile oil changes.