406oc.co.uk

Hello again

I drove my 406 2.2Hdi the other day at around 85-90mph (very quiet roads here in France...) and notice that immediately after this short burst at speed the engine felt as if it was 'wobbling'. The effect last for for several minutes and only seemed to disappear after I slowed down to around 70mph and maintained this speed for about 3 miles.

I'm pretty sure that my lower engine mount is on it's way out from the way the engine rattles on startup and stopping - could the mount be causing this wobble at high speed aswell. Already had a new DMF fitted and new auxiliary bits so pretty sure it's not those.

Any suggestions welcome...

Lord knows I don't like the sound of that rattle, sounds like something's loose (who changed your DMF? ). If it is your bottom mount I'd be worried about it fracturing the flexible section...

My rear mount was completely shot but never produced a 'wobble' whilst driving at speed except perhaps when rising over a crest in the road when the weight was lifted from the front slightly but then I still felt that a bit when the mount was replaced

Are you sure it's not just wheel balancing?

Ooh, a short loud chirp/chatter/squeek on start up does ususlly point to the DMF but you can reproduce some of the noise by driving slowly and bringing the clutch in/out sharply to produce a similar chatter/chirp/squeek (the things we have to describe eh? )

Mine was doing something similar on a weekend jaunt to France a week or so back - just between 130 / 135 kph! I noticed it only did it some of the time and I can't seem to reproduce it back in the UK
Had a really bad verison of this about a month back, which was down to a lumpy osr tyre. When I noticed it in France my 1st thought was I hadn't completely cured the problem, but I began to wonder if it might be just some road surfaces. It seems fine now I'm back home!

The noise you describe could be aux drive belt pulley, (I know you said it's been done), but you can eliminate it easily by removing the aux belt & seeing if the noise goes too.

Thanks for all your replies Chaps.

Got it booked into the Pug dealer in Cognac next week (who did all the previous bottom pulley/DMF stuff) for a diagnosis - they have a rolling road and said they can run it up to 150kph (95mph) if necessary.

406gtx wrote:they have a rolling road and said they can run it up to 150kph (95mph) if necessary.

Wow! how cool is that

Welly wrote:Wow! how cool is that

Yeah - their garage is bloody huge - it's got 8 bays and there must be at least 20 mechanics on site - mind you every third car here is a Pug...