Alasdair1

I did use redex and wyns but they didn't make much difference. The Forte one was more expensive but got good reviews and it worked. Good tip in puting a tank of premium diesel in from time to time. My local garage has a pump now so may give it a try. I never thought of that I assumed it was for performance diesels. Alasdair

If its still making black smoke try a bottle or too of injector cleaner in the fuel and perhaps replace air filter. My old octavia exhaust was a bit black and sooty but I used Forte diesel injector cleaner that I got from my old mate at his garage. Took a couple of tank fulls but cleaned it up. Alasdair

I readf that Mr Muscle is death to alloy. I was going to try it but was worried I would damage alloy parts on turbo. Think the best option would be to either strip down and clean and recondition yourself or replace with new or good second hand turbo. I was lucky as it was the actuator itself that was ssticcking,

Hi have a 1.6tdi and since I bought it revs at idle have been variable. I originally thought it was running high (1100rpm) due to being cold and would eventually drop once upto temp or perhaps regen cycle. Car starts at 1100 and normally drops to about 800-900rpm eventually Itakes a while especially when cold) but today the car was warm (90C) and I noticed when in town that the car was slightly accelerating in slow traffic. I was in second gear and it didn't feel right. Checked revs and they were 1200rpm with foot off pedal and the car seemed to want to accelerate by itself. Hit brakes and pressed clutch and it seemed to cure itself and revs dropped to 800rpm Any ideas what the problem might be. No fault codes stored or warning lights on dash. Car runs very well apart from slight wobble at 40mph which I still havent found out why plus a few knocks and clonks etc from I assume drop links/bushes and to top it off a dodgy wheel bearing appeared this week. Going to service and cure clonks/bearing this week. Winter is hard on cars. Just worried it will self drive into the back of someone. Where do I start to look? My old 1.9tdi never did this Hope the above makes sense Alasdair

Had the same isssue with an octavia. Low coolant sporadically but level ok. I bought another tank but never got round to fitting it and since then its cured itself. The metal prongs can get dirty/coroded and cause false singnals.

Looks like the Xtool vag401 is now discontinued. Pity because it didn't need batteries or a smartphone for it to work. Was hoping to get another one so I could have one in each car as they were really cheap. Not sure what their new versions or if theres something similar.

I bought a cheap code reader XTOOL VAG401. It was only £35-00 and I had my doubts but it actually works. Reads and displays codes and can reset them too. Its a bit slow and I havent used it enough to get the hang of it but it now lives in the glovebox. Was going to get VCDS but was a bit short of money. Your problem may be related to an accelerator drive by wire fault?? which I am afraid is well out of my comort zone. Alasdair

Check accross the battery with engine running with multimeter in DC mode. You should get 13.5-14v Change to AC mode on meter to see if there is any reading. If you get an AC reading then the regualtor is probably shot. The fact that you get a spike in voltage when revving does point to worn brushes but worth a quick check before removing alternator. There is also a very slight possibility that the belt may be slipping?? Alasdair

The exciter wire goes from the alternator I think marked L on the alternator to the back of the cluster/battery light (might be blue). There is another marked DFM which I think is a voltage sensor wire that goes to the ECU. The third goes to the battery. Under the car in front of the gearbox theres a few cable joins on a bracket below the starter motor if I remember right. Alasdair

Had the same problem with my BXE but it was the actuator that was sticking causing overboost and random limp mode. Turbo made a high pitched whine/whistle etc but disapeared once the actuator was freed up. I sprayed all I could with wd40 and manually operated it back and forward until it moved smoothly.

I had the same but the previous owner had upgraded headlights to 80/100w which eventually fried the wiring where it connects to bulb and also took out the fuse connector. Hope its just a blown bulb/fuse Alasdair

Could also be worn brushes in the alternator. It may manage to charge at higher revs on longer journeys but not at start up.

If it hasnt been done for at least two years it may be the problem. Enough fuel getting through for idle and low revs but not enough when you put the foot down. My old local garage when servicing changed all filters annually and not by mileage. It only takes a fill up or two of dirty/contaminated fuel. I recently did my 08 1.9tdi and the fuel filter was almost blocked. It had a weird jelly like substance in it which I eventually found out is a weird bacteria/algae diesel bug that can grow in diesel. Normally found in marine diesels. I also had in my old tractor. No idea where it came from although I normally get diesel for boith at our local garage who have recently had their tanks replaced???? Treated the system with a marine diesel additive and so far so good Hope its as simple as a new filter Alasdair

If its possible then when fitting winders I normally make sure the winder handle is vertical with the knob at the bottom. I had an old volvo that the windows kept opening slightly when driving probably due to gravity and vibration. I changed the angle of the winders and they stopped opening when driving. Hope its a simple fix/conversion

If its the DMF failing you can get a rattle as well as vibration. I have had one that rattled on start up but gradually settled down when driving. You can also get a judder when at clutch biting point. What mileage has the clutch done? I have read its possible to remove starter and use an inspection camera to look inside the bell housing. Alasdair

DMF is a dual mass flywheel.When they fail they can rattle and also cause vibration. If the noise goes when clutch is pressed then it could be a bad release bearing but also the gearbox. If you can hear it while driving then press clutch and freewheel. If its still there then I assume Gbox. if it disapears then I reckon its a clutch DMF issue Alasdair

The original airbag ecu will have a part number/serial number on it. You could try a second hand one with the same numbers if you can find one. It might work. Replaced a complete ECU on an old toyota and got away with it. If there was a fire it could be cable damage but it might be worth checking and cleaning airbag ecu contacts. Be careful you don't set any off. There will be a way of draining voltage/charge in system of before removing anything.

Could be the camshaft sensor is failing but it might be worth getting timing checked just in case there is a problem developing with new chain. I would perhaps change the camshaft sensor to rule it out.

Maybe fuel related? Has the fuel filter been changed recently. Could be partly blocked or at the moment here frozen. Alasdair

May have a DMF thats failing. or a failed rattling release bearing. Does it judder at all when taking off and does the noise disappear when the clutch is pressed? Alasdair

There a lot of things on Utube that are useless or wrong/outright dangerous. I learnt old school by watching proper mechanics and haynes manual plus a bit of trial and error. Just did my first FWD clutch on my sons Fabia. Done plenty of RWD but it ook me ages but got there in the end. Mechanicaly I can do most things but I'm struggling these days as theres so many sensors and electronics involved. Bit out of my comfort/knowledge zone. Not sure if the new injector would have to be coded with vcds? or if your mechanic already done it. If its not coded I assume it would be ok at idle but may be way out at higher revs. Hope the next scan pings something up. Not sure where you are but have a look locally for a vw/skoda specialist. We have a couple locally who know the cars inside out. Alasdair

Let us know. I have a similar problem with my octavia 1.6 tdi Get a weird wobble/shake at around 40 and when accelerating. Seems to be better when I press the clutch and coast but some days its worse than others. Have checked all bushes and tyres/suspension and drive shafts. Was thinking it might be DMF but its ok when I take off and at lower speeds. I have no engine light (yet!) Alasdair

Did you change the camshaft sensor and knock sensor either might be sending false info to the ecu. By what you have said you seem to have covered everything. Hopefully someone else on here will have an idea where to look. Alasdair

If its the manifold I would think the fault would be present all the time unless its temperature related ie sealed when warm but not when cold which is unlikely the reason for 16555 code. Could be a faulty 02 sensor but I reckon that would put eng managment light on judging by the symtoms. The other thing it could be is the MAF but again I would think the eng manag light would come on. Sorry I cant think of anything else to check. Alasdair

Not sure if its any help but the clicking if it is a relay could be one for a fuel pump. I its contacts are failing it would explain the non start randomly. Think they are near the fuse box but under the dash. Alasdair Dont know if you have but it might be worth checking for fault codes? Alasdair