A knocking has just started at 800rpm idle which goes away if revs are raised to 1000 or clutch is pressed in.  It's a 2007 registered BLT engine. At just 49K miles, I'm pretty surprised but could this be the start of the dreaded DMF failure tell tale signs?

 

I am really beginning to regret buying this car as after just a month I've had to shell out on cambelt/waterpump, EGR cleaning, Intake manifold cleaning, replacement of failed switches., EGR delete (to avoid the clogging up of the intake again).  The car was one lady owner (hubby was a former Skoda mech tech), and all signs are that it's been driven like Miss Daisy (discs all good, cloged EGR suggests not a lot of revs regularly given but could equally be lots of short trips or stop start town work).  

 

Question is, if it is the DMF on its way out, is it worth replacing both the turbo and DMF at close on 50K miles (as at some stage the KKK will need replacing anyway).  I had planned on a PD150 Garret job at some point in the future and it seems sensible to do it with the clutch/flywheel and sell the original turbo to try and recover a little cash back.  I would only do this if I thought that I wouldn't have to shell out for any more major expenditure for at least another 100K miles, otherwise the car isn't worth spending the hard earned on.  Sickening really as the car looked, sounded and drove perfectly on the test drives and subsequent inspections which was only 400 miles ago!

Never mind.  Had it checked;  it is DMF and at just 49K miles.  Not a happy bunny at all.

that seems a low idle which I am convinced aids early death mine is at +900 and has "hunted" from new, a few more revs just seems to stop the flywheel overtaking the engine -I always keep my foot on the gas at lights etc--guess Miss daisy hasn't helped either

I agree.  I think there's a VCDS option for raising idle to 1K revs.  Unsure why its not set at this from the factory unless it's emissions related?

 

Bizarrely, after several days of loud knocking, it's just stopped so who knows...possibly just a little gummed up.

Joel very recently posted up a quick guide on how to raise the idle speed through VCDS-Lite. Dan and myself both have BLT engines however, and found that you could only really raise it up to about 880rpm. It does make a difference though.

 

Here's the thread...

 

http://www.briskoda.net/forums/topic/326816-uprated-dogbone-mount-a-little-tip/

 

 

I wouldn't get disheartened about the flywheel. DMFs, clutches and turbos have been known to die very early on some cars. I'm afraid it's all luck of the draw! If you replace the DMF and clutch then apart from the turbo you should have many miles of trouble-free motoring other than the usual wear and tear.

 

Your flywheel might not even be on the way. Mine's rattled and knocked for the best part of 70k miles now! I'm running over 300ft/lbs and I actually CAN'T kill it!!!

Brilliant, thanks Alex, I'll give that a go.  Currently about 750 to 800 RPM which does seem a little low.  If the clutch/DMF did go, I'd simply replace it with another stock SACHs unit.  They seem pretty good really and I don't plan on running anything over 160 BHP on the KKK.  I have a PD150 turbo lined up in the event the KKK goes South. That could well be some time off with luck. I initially tried a Quantum performance map and the torque was too much for the car really to put on the road effectively.  Wheelspin in 3rd from 40mph...insane punch.  Now mapped back to the economy (green?) map and its fine at that.   More than enough urge. When the PD150 goes in, maybe then I'll lift it a bit but I want to keep it as close to stock as possible for reliability.

Never mind.  Had it checked;  it is DMF and at just 49K miles.  Not a happy bunny at all.

 

A 7-8 year old car with 49k on the clock will more than likely have spent a lot of it's time urban driving. So I wouldn't be too surprised to see a clutch/dmf starting to show signs of failure. Having said that unless your having problems driving it or it's making a real racket I wouldn't be too quick to replace it. They can make noises for years and still work as said above. I'd wait till it goes personally!

Stick with it fella, I've heard a lot of cars on here have had turbos blowing and clutches burning out, these are the joys of motoring in an icon car, what other car out there is as economical as these one minute and you can have a blast the next. If driven sensible you can get 500 plus miles out of a tank of 50 litres. Priceless. Lol.

Funnily enough, the knocking has died down this past few days, so I will be leaving it for now, despite the mech saying it was the dmf.  My only issue to sort is why the car continues to smoke at start up. At that mileage, I can't see an injector being out or a seal going (there'd be other symptoms).  Clutch has returned to being quiet as a church mouse (albeit one dancing on the organ peddles!).  

With regards to the idle speed.

 

It can be adjusted.

 

800rpm is within spec I think but probably on the low side.

 

Best thing I found is to adjust the idle up to about 900rpm then bring it back down in increments till you find the sweet spot where the idle is smooth but without it idling higher than it needs to.

 

Mine likes 830rpm.

 

Phil

I can only try it with foot on the throttle and 1000 revs is very smooth but even 900 is a big improvement.  I'll see what we can do when I drop it off in a few days time for the inlet manifold removal/cleaning (this on its own isn't doing the car any favours...the inlet manifold is incredibly coked up).

With regards to the idle speed.

 

It can be adjusted.

 

800rpm is within spec I think but probably on the low side.

 

Best thing I found is to adjust the idle up to about 900rpm then bring it back down in increments till you find the sweet spot where the idle is smooth but without it idling higher than it needs to.

 

Mine likes 830rpm.

 

Phil

interesting maybe mine is too high    ---with all the crud out and the maf checked out it should be a different car --don't forget to drain the inter cooler too