Annoying vibration when pulling away....

Pompeydave

A2OC Donor
Hi all, sorry another plea for help! I've got a 1.4tdi with an annoying vibration- a sort of a 'brrrrr' type noise that's coming from somewhere in or around the engine compartment.

It only happens when pulling away- you can revs the nuts off it on the drive and you don't hear that 'brrrrr' noise. It also only does it at low revs and it does it again as you go through the gears.

Once you reach about 1500 rpm it disappears, only to reappear briefly when the next cog up is selected.

There's nothing obvious in the engine compartment, nothing loose etc. I was wondering if it's something to do with a heat shield vibrating against the exhaust maybe? Any idea's where it might be coming from?
 
Could be any number of things. If you say 'vibration' I doubt it's a heat-shield. There is also a heat shield next to the fuel filter than can corrode - but it would rattle. Check the engine tray is properly secured. If the vibration is linked to changing gear it could be a worn transmission mount?
 
Ok, thanks for the advice, I'll check out the engine tray. Got to find it somehow as it's driving me nuts :(
 
I had an annoying vibration/rattle that occured around 1300RPM for a while. It turned out the bracket holding the MAF in its proper place above the arch of the engine mount had snapped, which meant the MAF had dropped by about 1CM and so was now resting on the engine mount. Even if your bracket isn't broken, ou might want to check the clearance around here - although I've replaced the bracket (annoying job as involves removing the brake fluid reservoir!), there still isn't much clearance and I was getting the occasional buzzing sound, so I've subsequently cable-tied some foam around the underside of the MAF, which has now cleared that.

Unfortunately I've now noticed a new rattle in my car which is the OpenSky - the front pane is rattling slightly when fully closed. Argh!
 
Aha, interesting! What flying scot is describing is exactly the same (as in when it's happening) as my problem. The only difference is the noise itself as my is a repetitive 'brrrr' rather than a single noise he describes. Where on the car is the bit that he says needs buffering?
 
Think I might possibly have identified the source of this noise. Trawling through the excellent 'how to' guides, I've stumbled across the 'Gearstick rattle at idle' problem:

http://www.a2oc.net/forum/showthread.php?12595-Gear-stick-rattle-at-idle-problem&p=95933#post95933

The noise in the You Tube vid is exactly the same as I'm getting. I wonder if my gearchange cables are causing this problem?

The gearchange is very tight all through the gears. Would it be reasonable to assume that this is an indication of all not being well?
 
*sigh* Sadly, I still have this problem. Haven't had the time in the last since the last post to investigate further, but a complete suspension strut and drop links change hasn't cured it. It sounds like it's some part of the engine knocking against something in the engine bay, or it's coming from the transmission somewhere. It's not there at idle or when the engine is revved hard in neutral, only once I pull away, and it seems to disappear from about 1500 rpm upwards, but might just masked by road noise as speed increases.

I don't think it's the ARB, as everyone else seems to report a knocking noise ocurring whenever going over a rough surface or on hard left or right lock. Any idea's anyone?
 
Hi all, other issues have meant that this problem has been on the back burner almost since buying this car more than two years ago, but it still haunts me daily. I've now checked the ARB bushes and they're absolutely fine. I seem to remember reading somewhere on here that Audi had a retro fix for a couple of metal pipes that were found to rattle against something else as mileage increases with age. Mine has done 188k now so must be one of the higher milers out there. Does this Audi fix sound familiar to anyone?
 
I can't look at that thread for some reason- I get a message stating that I don't have sufficient privileges to view it?
 
I can't look at that thread for some reason- I get a message stating that I don't have sufficient privileges to view it?

Not sure why that is happening David, I can see it OK but it includes a few posts from former member 'Emm' who left the club in 2008 and wanted all his posts deleted so that may or may not be the reason.

I'll see if I can cut and paste the info onto a PM for you.
 
Ok, thanks Murdo, hope you're well? I don't think the recall Spike mentions is relevant to my car. The recall was for: "1.4 TDi engined cars across the VAG range built during 2004 and related to the tandem pump bolts." Mines a 2001 so sadly I don't think this is the source of the problem. I'll have a look at the pipes to see if there's any movement though.

There was some mention of the MAF sensor mounting break causing the sensor to rattle against an engine mount. I'll double check it today, but I've been through the engine bay with a fine tooth comb twice and found nothing so I'm not holding my breath....
 
Bloody hell, success! dan_b, when I originally read your post re MAF sensor bracket woes, I checked the bracket on mine and found it to be ok, so I discounted the MAF as a source of the problem. Today I went out and looked at it again and it is very, very near to the engine mount. So in an unscientific but effective experiment, I stuffed a rag in between the sensor and the mount, drove it down the road and wahay, no more Brrrrr noise as I pull away!

This has been torturing me for two years now so thanks everyone for the suggestions, particularly dan_b of course :)

This only leaves one query, did Audi revise the MAF sensor mount to allow more room? I'm sure I read that they did somewhere?
 
Bloody hell, success! dan_b, when I originally read your post re MAF sensor bracket woes, I checked the bracket on mine and found it to be ok, so I discounted the MAF as a source of the problem. Today I went out and looked at it again and it is very, very near to the engine mount. So in an unscientific but effective experiment, I stuffed a rag in between the sensor and the mount, drove it down the road and wahay, no more Brrrrr noise as I pull away!

This has been torturing me for two years now so thanks everyone for the suggestions, particularly dan_b of course :)

This only leaves one query, did Audi revise the MAF sensor mount to allow more room? I'm sure I read that they did somewhere?

Thanks fellas i had the same problem with the MAF vibrating against the engine, No more noise when i pull away or back of the accelerator

All the best
Whiskylee
 
Bear in mind that if the engine mount is allowing that amount of movement, so as to cause vibration against the MAF, it's likely that the mount wants replacing before too long. Another possibility is that the mount may not have been replaced correctly following a cam belt service - it needs undo-ing to get the old one out and the new one in.

Cheers,

Michael
 
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