Throttle damper on a VR6 - is mine set too low or broken? VIDEO INSIDE!

[mookie 0]

http://www.youtube.com/watch?v=wL4rTY-9ITU&feature=youtu.be

 

I took this little video of the throttle on my VR6. It's veeeeeeeery jerky at low revs/speeds when you take your foot off the gas, like kangaroo-ing out of petrol time. As you can see in the video, when the throttle is released, it slams shut quite hard. However the little damper device (not sure what it's called) does provide SOME cushioning but seems to be happening too late, i.e when the throttle is already shut. I noticed however that it can be screwed in or out to increase it's height/distance from the throttle. On mine (not sure how easy it is to see) it was about halfway down the threaded bolt end into the bracket... it actually looked a little like it had been moved to accomodate the removal of the inlet pipe work around the throttle opening.

 

I've since unscrewed it by about 50% less thread so the throttle now hits it sooner and the butterfly in the throttle almost shuts, leaves a crack of a few mm, then slowly closes fully. A quick drive and it is a lot better in most situations now, but still can jerk say in 3rd at 15/20mph as you lift off the gas.

 

My big question therefore is... is there a specific position this damper should be set to in terms of how soon the throttle hits it before closing? I still have a couple more turns left on it before the nut on the end would struggle to hold it still. Does anyone have a photo of how this should be setup? I feel it isn't broken as I've seen described else where, but that maybe it needs fine tuned a little more to get the softening effect just right, but obviously I don't want to screw up the idle if it instead lingers too long with the throttle open.

 

Any help greatly appreciated.

[Roger Blassberg 0]

The set-up is described in the Bentley manual - if you haven't got it, I'll scan the relevant page and send it (assuming I can work out how to attach it to the reply !!).

 

I had precisely the same problem and symptoms of jerky off-throttle slow running. This is what I did;

1. Replaced throttle damper and set it up as per Bentley. This made some difference.

2. Cleaned out ISV and made sure there were no air leaks on induction side.

3. Did a basic settings to ensure that the throttle position sensor was coordinated with the ECU. This helped too, but not completely.

4. Got a good second-hand MAF; (they are not necessarily goood just because the engine doesn't stall if you disconnect it at idle.) Make sure the connector and the platinum wire are clean, and check the wiring for continuity back to the ECU. This was a further improvement, but still had occasional stalling when de-clutching from over run conditions (like throttle closed going downhill).

5. Disconnect 42 pin connector on the side of the cylinder head (with the ignition OFF !!), clean pins and socket with contact cleaner and re-seat the connector. This significantly improved idle and general running. The electrics for all the injectors and for the ISV go through here so any bad connections are bad news.

6. Had all injectors ultrasonically cleaned and filters replaced. FINALLY !! Perfect idle, no stalling, greatly improved starting and fuel economy. For good measure also put in a new set of standard issue NGK spark plugs.

The difference is like night and day - it will trickle through traffic in 4th gear with no snatching and surging and, best of all, no stalling at junctions.

 

Try these. In the meantime, I'll try to remember to send you the damper set-up procedure

 

RB

Edited May 28, 2012 by Roger Blassberg

[24V Renshaw 0]

Excellent post.

 

Jay

[mookie 0]

Thanks for the reply! Good little check list for me to go through there. After winding the damper out a bit more I get virtually no jerks... not sure if when it does jerk now it's because it's to high gear and too low revs ha ha but I really want it running perfectly rather than 'about right'. I've borrowed a fault reader just to eliminate anything really obvious and then go through the list above.

 

But it the clutch now 'grabs' a bit changing gears which I think might be because the throttle is closing completely, too slowly now, and so is like changing gear wit my foot very slightly on the gas? I think... But anyway I'm going to try winding it down again a little again.

[Critical_Mass 10]

Thanks Roger. Got this issue too and its so annoying. But i need to start with getting a new throttle damper pot.

[Roger Blassberg 0]

Gaz,

They are available, on back order but stupidly expensive - over £50 from VAG !! I cannibalised a throttle body I got from ebay, and got a spare TPS into the bargain.

 

Mookie

let me know your email address (by private message if you prefer) and I'll send you a print of the set-up procedure for the damper. From the youtube video it seems to be not totally broken, there is some damping there but not over its full stroke.

 

Best wishes

 

RB

[mookie 0]

Gaz,

They are available, on back order but stupidly expensive - over £50 from VAG !! I cannibalised a throttle body I got from ebay, and got a spare TPS into the bargain.

 

Mookie

let me know your email address (by private message if you prefer) and I'll send you a print of the set-up procedure for the damper. From the youtube video it seems to be not totally broken, there is some damping there but not over its full stroke.

 

Best wishes

 

RB

 

Massively appreciate the email Roger! Helped a lot!

 

However I still have bad jerks... and I have noticed it's worst when going off or on the throttle going down hill when the car was/is engine braking. Almost like it gets a momentum up of shakes! Which got me thinking about why that be going down hill? Weight, gravity... and the engine movement in the bay being affected. I'd previously replaced the gearbox mount as it sprung a leak, but gave the engine a good push and pull when I got home tonight and there is a clank/knock coming from the front mount if you rock the engine side to side or push up with the front of the inlet manifold. So new front mount is getting put on this weekend as hopefully that just be it if the weight of the engine is able to shift about in that direction? Must be worth a go!

[24V Renshaw 0]

I am running a group buy on poly engine mounts front and rear for £64. Makes a huge difference to the movement.

 

Jay

[mookie 0]

What's the likely ETA on them? I just had a read of the thread and they look really good... I'm really tempted but this mount needs done ASAP sadly...

[24V Renshaw 0]

To be honest once I have maybe two more people I will order them, so I would guess a couple of weeks or so. Worth waiting for.

 

Jay

[Critical_Mass 10]

Gaz,

They are available, on back order but stupidly expensive - over £50 from VAG !! I cannibalised a throttle body I got from ebay, and got a spare TPS into the bargain.

 

Best wishes

 

RB

 

Yes i heard Roger, cannot believe thye're so expensive. A new one will be a last resort i think. Will check out ebay for throttle bodies can always sell the throttle body on so recoup some cash :D

[24V Renshaw 0]

I just bought one of these as I am not convinced mine is working properly.

 

http://www.ebay.co.uk/itm/AUDI-VW-16V-2-0-ACE-VR6-THROTTLE-WOT-SWITCH-SENSOR-/170846546835?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item27c73f6b93

 

£15 and its the right part.

 

Jay

[Critical_Mass 10]

Ah Cheers Jay. I take it you offered him teh £15 and he accepted? Have to snap one of these up.

[24V Renshaw 0]

Nah offered him £12 LOL

He came back with £15 which I accepted.

 

Jay

[Critical_Mass 10]

Ill do the same ;-)

 

Cheers

[mookie 0]

To be honest once I have maybe two more people I will order them, so I would guess a couple of weeks or so. Worth waiting for.

 

Jay

 

I so wish I could... I'll need to see how my funding goes as I need a few other bits first :(

[24V Renshaw 0]

Fitted my new one yesterday and its made a noticeable difference. No more "snap" of the throttle when you let off the power.

 

Jay