Strange Judder under Acceleration

[martyn666]

Hi,
Hope someone may by able to help with this one:
Car is a 1998 Mk3 Golf Estate 2.0 8v engine AGG
I am having the following problem with it:

Under acceleration no matter what road and/or engine speed I get a very noticeable judder through the whole car, nothing at idle and/or deceleration coasting.

I have changed the inner CV joints and front engine mount in the hope that it would cure it but I am not happy driving it at the moment.

It has recently had a full service including: cambelt, plugs, leads, cap, rotor arm, coil.
I have had problems in the past of idle and cutting out and have changed:
Engine speed sensor
Both dodgy relays
Cleaned out breather system and throttle body.

I'm a but stumped - could it be the clutch letting go? But it is not slipping.

All bearings and bushes are ok - wheel alignment is ok as are tyres and pressures.

Help - before I lose my marbles.

Thanks in advance,


Martyn.
:confused:

[SammoVWT]

What about gearbox/crank?

[martyn666]

How would I go about checking the crank/gearbox?

Are you thinking maybe the bearing on the crank behind the flywheel is going?

I have recently checked the gearbox oil and its all fine.

[SammoVWT]

Sort of yeah but thinking on it more an engine mount is worth looking into

[martyn666]

I have changed the front one - which had a little play in it and the problem still persisted.
I could change the rears too - but I'm loathed to spend more money on it TBH.

I was kinda hoping there was a simple fix that I had forgotten to check :)

[Ignacious]

I had the same problem in a 2.0 fitted with the auto box..turned out it was the gearbox rear mount,have a look on ebay for engine mounts..look for VOLKSBITS ....got mine for 16 quid incl postage..vw wanted 53 quid!!!!!nuff said???:beerchug:

[martyn666]

Oh that's worth a shot - I picked one up today for £15.

Easy to replace? Any tips?

Cheers

[Ignacious]

yes,not too difficult as long as you have access to a trolley jack or bottle jack,just support the engine,crack off the bolts,remove the mount and swap over.Give the bolts a good soak with penetrating oil/wd40 etc..use a 6 sided socket to stop the bolts from rounding and just be careful not to shear or round the bolts.
The only other thing that may also be worth having a look at is wheel balancing??Is the vibration through the car,steering wheel,pedals,brakes ??
Hope the mount cures the fault..my was shot to bits and made it a great deal better!!Tim

[finfin1]

Hi
I see this thread started back in Jan '11, so you've either solved the juddering or got another car...

In case this should be of any help for a mk3 owner doing a search for engine mounts (or wobbling/juddering under load) my recent experience might help. Mine is a simple 8v 1.4 ABD Mk3 but I'm told the mounts are the same for all the Mk3 engines.

My Mk3 had developed a wobble under load, at its worst around 50 mph, and for some considerable period before this I was noticing a lot of horrible slack on quick acceleration/deceleration. My local GSF told me it was probably the engine mounts as they do tend to "go", most commonly the front one. Inspection of the visible part of the rubbers (after peeling back what I could of the rubber covers) didn't give any real sign of trouble, though the front one did seem to feel loose in it's socket and the engine could be rocked about all too easily for my liking with visible play on the front mount with a little on the rear. When I first took a look at the rubbers I thought the problem was obvious as I saw lots of what I thought were splits in them but these are holes and they are meant to be there - as the new ones showed!

Anyways, I decided to replace the front and the rear engine mount as these were the two points where I could see obvious movement. Doing this has solved the wobble and slack but I'll probably get around to doing the rear gearbox mount as well at some point soon.

Having no access to a workshop pit I had to use my trusty ramps and made sure to chock the rear wheels really well with the handbrake on tight and the car in first gear. As it turned out in my case the offside (UK) rear mount required being under the car for long periods : ( Haynes advise disconnecting the battery negative cable which I did. I used a trolley jack with wood block under the gearbox/bellhousing mating surface for the front mount and used a wooden beam mounted across the engine bay (as per Haynes) tethered tightly to the engine lifting eyes to support the engine to do the rear (offside (UK) ) but I also used the trolley jack with a wood block under the sump (a bit dodgy as there's probably not much strength in the sump pan) to raise the engine enough to give some free play to the rear engine to mount bracket. Worked for me but if you've got a heavier engine than my 1.4 it's probably best to use a proper engine hoist and raise the engine from above. I found the front mount reasonably easy to do but following Haynes got me swearing badly as after following its steps for front mount removal, I couldn't undo the allen/hex retaining bolt underneath the mount after having removed the engine bracket as it is this that stops the upper part from revolving!! If you've got someone else to hold the upper part, or something else to stop it revolving then this might not be a problem for you. Otherwise, slacken off or take out the lower bolt before removing the bracket. The only other trouble I had with the front was getting the bracket to line up with the holes for the through bolts on the engine following replacement of the front mount. Having a mate to jiggle the engine / adjust the jack supporting the engine would help a great deal with this.

The rear offside (UK) engine mount was a challenge. I removed the injector/air filter covers/hose complete to aid access. In short, there are three no. 8 hex/allen-key bolts holding the rear bracket to the engine. The top two are relatively easy to remove but the one underneath is a pig to get to. There isn't a great deal of space between the head of the bolt and the mounting and you've got a driveshaft and other parts in the way trying to work at it from under the car. I couldn't get to this bolt from above. I ended up grinding down an 8mm allen key to about half the length of it's short end to fit the space between the bolt head and the mount. Perhaps there's another and easier way to get this bolt out - a special vw tool? - but I couldn't find a better DIY way. I found this bolt really tight and it took a lot of effort to undo. A hollow metal extension tube placed over the shaft of the allen key would be of help in getting the bolt loosened but I'm not sure there would be much room for leverage. I used side of a club hammer : )) Took several hard whacks to get it going though.

The rear gearbox mounting does look a lot more simple to do.

Haynes gives the following torque settings:

Front block bolt: 50 nm / 37 lbf ft
Front bracket bolts: 50 nm
Left rear mounting bracket bolts 25 nm / 18 lbf ft
Rear block-to-body bolts 25 nm
Right rear mounting bracket bolts 25 nm
Through bolts 50 nm

[pmartin13]

It sounds to me more like your ignition timing is out, needs setting via vagcom data group 7, timing light is no good.
Hope this helps

[finfin1]

It sounds to me more like your ignition timing is out, needs setting via vagcom data group 7, timing light is no good.
Hope this helps

Sorry for delay in replying. Thanks for the suggestion. It could be an ignition timing fault but I never had any vibration until I changed the mountings. Wouldn't hurt to get the timing checked though, so will get around to this soon. Thanks again.