Hello Everyone.

I've done a search and read quite a few posts on various vibration causes and noises. I'm not quite sure what's going on with mine though..

This morning I paid close attention to how it was behaving.

At idle it's a little vibratty... not allot, just a smidge more than it used to.

At 30mph in 4th (down hill of flat) it's about the same as always when just pootling, not accelerating.

Accelerating briskly upto 30 in 1st/2nd it's ok in the lower end of the revs but as you get up past 15rpm it's kinda buzzy, it's pulling ok but just vibrates/buzzes as it does it.

20 to 50 Briskly in 3rd starts ok, then gets quite buzzy but settles a bit as you let off to stay at 50 but still buzzes / vibrates more than it did.

Motorway is more buzzy at all speeds but obviously gets worse when you go to overtake with power. Before at motorway speeds you could forget it was a diesel, now it reminds you.

At motorway speeds recently it's seemed just a little less willing at the top end of things, I put this down to the change in fuel and weather conditions, but could it be linked if it continues?

The Vibrations are going through most of the car and strangely not effecting the steering wheel or pedals any more than anything else.

I've topped up the oil and re-greased the MAF connector, put in the millers and a decent tank of fuel. It's normally fed BP ultimate but over Christmas it got 3 tanks of the norm with out any additive but they should've long gone through by now.

The above has made it easier to start and given me a little more mpg.. but it's still got this buzzing going on.

So, could it be.

A. Mounts?

B. MAF?

C. DMF?

D. Something else or all of the above

It's not Making any "nasty" noises, and it;s not really a "shake" just kinda vibratty-buzzing.

Thanks

Rob.

Edited 19 January, 201016 yr by Rob.

Could this be a wheel bearing?

That said, that wouldn't explain the slight extra vibrations when stationary. Could that be the average fuel & cold though?

A bad bearing would lower MPG wouldn't it? Could that also explain the slight sluggishness at the higher end of the speedo?

I ask because I did suspect a bearing a month or two ago as got a drone on the motorway because In Febs snow I clouted a kerb but the bearing survived unlike the wishbone and drive shaft. I haven't heard the tell tail drove since but maybe that's because it's vibrating instead now?

The guy that fixed it was surprised the bearing survived and told me it;s life would be shortened.

How can I check a bearing?

Edited 19 January, 201016 yr by Rob.

You can check a wheel bearing by lifting the relevant corner into the air and checking for any play in the wheel towards / away from the hub, I think.

The fact you're getting it at idle suggests something to do with the engine rather than the transmission, although I suppose DMF could still be the problem. Check on here for symptoms of DMF failure, but it tends to be a harsh vibration under heavy acceleration AFAIK.

If it's the MAF, try driving around with it unplugged to see if it makes a difference. If not, it's knackered.

Other than clonking, I don't know of any symptoms of problems with the engine mounts...

HTH

It's defiantly not a heavy or harsh vibration.

I do get clonks every so often when changing gear so maybe my gearbox mount is getting worse?

When an engine mount fails, would it not pass the vibrations it was suppressing through to the chassis?

I hope it's not MAF related our I'll get suspicious of the Cage Mod. I'll try disconnecting it but after I re-did the grease it fired up almost instantly first thing this morning.. and that's a notable improvement over the last week so don't think the problem lies here.

EDIT: UPDATE.

Just been over on uk-mkivs.net and they seem to get these similar vibrations when the dog bone fails.

Anyone had a dog bone go on a Fabia vRS? What's it like to drive?

There's also a couple of threads saying that inner CV joints can cause this. This is particularity relevant as the drive shaft and outer Joint were both smooshed by the collision earlier this year. Maybe the Inner joints failed as well and it's not the bearing? Wheel wobbling is required.

Will a shaft wobble if it's joint is cream crackerd?

Edited 19 January, 201016 yr by Rob.

Right... Need more help.

Disconnected the MAF and didn't notice it being any more or less vibratty but the EPC light came on, that is meant to happen, isn't it?

Drove a short distance with the MAF disconnected.. apart from it being in limp mode it seemed the same.

How many cycles/starts with no faults is it before the EPC light clears now? It doesn't seem to be in limp mode anymore now re-connected.

I'm not actually sure what this does or doesn't prove.. If it's not the MAF then it would seem as bad because the issue remains either way.. and if it WAS the MAF it would seem as bad because I've got use to it not reading correctly

How much worse should the car feel without the MAF connected, is it a "Wow, that's terrible" situation or is it subtle and if something else is causing an issue it could easily mask the difference?

If the car runs the same with the MAF connected as it does with it disconnected (but obviously badly in both cases), then it's a pretty safe bet the MAF's shot. With it connected, the ECU still gets a signal from it (after a fashion), hence the lack of a warning light until you actually disconnected it. I can't tell you how ling (if at all) it will be before the warning light clears, but I presume it will get the hint once a new MAF is in. I believe you can get reconditioned ones, but I might have imagined that...

Without wishing to rub salt in the wound, what mileage is your car, and do you have a panel filter?

it's done 61k, and no, no panel filter just the OEM one which was changed about 14 months and 11k ago. I know most people would say change it but could that really be the issue?

I don't think it's the MAF as when it was disconnected I had no power from kinda 2k upwards, As soon as it was re-connected it went back to full revs.

I'm still confused though because as I stated in my other post, we know limp mode cuts the power to keep things safe, but a disconnected MAF goes to a default setting. I have no idea which one the car was doing. When driving the initial push was the same but then the power would just thin out.

I've been on the blower to "Russel Automotive" in North West London who said to pop over and they'll give it a spin and see if I'm imagining it or not. They're a VAG specialist that have won Audi Driver Magazines Specialist of the year the last two years in a row so they should have an idea of how an ASZ should rev and feel.

It's so subtle ya see, It's only just a little buzzier/ vibratty than normal and I reckon if you didn't know the car you'd think it was fine and just a "Diesel". but I Know this used to be smoother, especially on the motorway. It's annoying because I know somethings not right somewhere but I sound like a mentalist banging on about it, lol.. oh well!

Is there anyway I can tell if an inner CV joint has warn?

Thanks!

Edited 20 January, 201016 yr by Rob.

I was asking about the panel filter due to the over-oiling contamination problem. Clearly not a factor for you. As for no power over 2k, this sounds like what I was experiencing when my boost pipe failed. Once the ECU had decided to put the car in limp mode, that is - prior to that, it was like driving an angry kangaroo!!!

AFAIK, you check CV joints by finding a large quiet space, and driving round on full lock, listening and feeling for any clicking / knocking. That or a strip-down, in which case you might just as well put a new one in! Then again, I believe they're pretty robust unless the gaiter fails, which can be spotted fairly easily without taking the car to bits...