Merry Christmas all.

My 2009 2.2Td4_e has developed a peculiar tapping noise that can be heard whilst the engine is running. As on the video here. Any clues? The engine has done 102,000 miles but serviced properly all the way, otherwise no issues.



Any help will of course be much appreciated, and rewarded with a pile of mince pies and festive cheer...!

Do you get any clicking when you turn off the engine. If so it could be the throttle body. FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

The alternator bearing/clutch...

Info and part number: https://www.drive2.ru/l/5318512/
Topic and another recording (on first post): http://lr-club.com/index.php?showtopic=113230

Thanks guys. It’s not the throttle body, I’m fairly sure. No clicking on shut down.

I’ll have a look at the alternator issue, that sounds plausible.

Just try with AC on and offf then to rule out that. FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Ancillary belt tensioner or tensioner pully or airconditioning clutch bering my guess wold be compleat ancillary belt kit

My belt tensioner failed just weeks ago, rare failure and no pre noise but rule out nothing I guess. FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Did you change the separate pully guide wheel

Is there one ? FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Last edited by Yorky Bob on 27th Dec 2017 9:53 am. Edited 1 time in total

Thanks all. I’m back with the car today so will check these various bits. I’ll check each component in turn on the belt route to rule each one out in turn.

I take it from your comments that the alternator has a clutch then, I didn’t realise that and assumed it ran all the time. How would I know when it is (and isn’t) engaged?

Not aware of that clutch myself but you will get loading as power demand changes. Suspect clutch ref is the AC. FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

Almost all modern alternators have a one way clutch built into the drive pulley to help smooth out vibrations when running. When the clutch seizes it makes the drive belt flutter and is quite noticeable if you look at the belt when the engine is running. The flutter also creates a lot of noise. The pulley is available as a replacement part but you will need a special splined tool to enable you to change it.

I also have a tapping/clattering noise which appears to be coming from the front offside of the engine when it is cold. After running for some time it goes away, but reappears after a few minutes cooling down. No clicking on shutdown. Any suggestions please?

TD4 2007 with less than 100,000 miles. Recently serviced by Halfords-type chain (in France).

[quote="dondiddy"]Almost all modern alternators have a one way clutch built into the drive pulley to help smooth out vibrations when running. When the clutch seizes it makes the drive belt flutter and is quite noticeable if you look at the belt when the engine is running. The flutter also creates a lot of noise. The pulley is available as a replacement part but you will need a special splined tool to enable you to change it.

Never too old to learn, long time since I changed diodes in one. Not aware of it being a common fault but very plausible. Old trick and be careful is to get a long solid screwdriver and put blade on unit body and then put ear against handle. FL2 MY10 TD4 GS traded in at 2 years
FL2 MY13 TD4 GS Current

[/quote] 1978 Laverda Jota. Stolen...
1980 Honda CBX1000 6cyl.
1978 Laverda Montjuic.
2010 Yamaha MT01.