2.0TDI seems to be missing, lacking power

[deano-1000]

Hi, My Passat seems to lack power or to miss-fire occasionally, a bit strange for a diesel. It has been in for a service and MOT at local dealer and while it was there I asked them if they could take a look, all they did was to plug it in and no fault codes were found they never even took it for a test drive. It does it at about 1200rpm in 4 or 5 at about 30-40 mph, just missing slightly, you have to hold the accelerator at a constant for it to happen, if you put your foot down it goes. I have noticed tonight on a motorway that it also does it at 2000 rpm at 80mph. Car has been regularly serviced and I have bought my diesel from the same place for the last 3 years of ownership. Only noticed it happening for last few months. It has had the emissions recall.

Anybody with any ideas?

I have used a diesel treatment and no difference.

[Crasher]

Not at all unusual for a common rail diesel, they are nothing like the old distributor injection units of old. The emissions recall, hummmmmm, that has been a lot of trouble, the number of cars we are seeing with problems afterwards is shocking. I would suggest finding a specialist to do a gentle performance remap that is in keeping with the car having a diesel particulate filter.

[deano-1000]

Thanks Crasher, I was afraid you would say that. It does seem to have been playing up since the recall, it was fine before that was done. Local dealer doesn't seem bothered, as I said earlier, they never even took it for a test drive to see for themselves. I've read other posts about it and how it can't be reversed and all the trouble it is causing with the ecu. I was hoping it might have been a easier fix like a sensor or something.

[Crasher]

It could be a sensor, the EGR valve, the recal, anything. As there are no fault codes stored the next step is to use the diagnostic system to view the live data and see if there are any clues as to the problem, you need an experienced tech to do that.

[deano-1000]

Thanks again for that Crasher. The car today had no issues at all to and from work, all fine, there doesn't seem to be any pattern to it. I did ring Advanced Tuning up earlier to see how much it would cost to get it remapped and he said he couldn't do it for a 2012 car and told me to take it back to VW and complain, apparently cars after 2008/9 the ecu scrambles any attempt to remap them which is why the recall cannot be reversed. This doesn't sound true as there is plenty of tuners advertising recall remapping, I only called them as they are a site sponsor and would know what they are doing, it was the Pontefract branch. I'll probably just wait for the car to get worse and develop a fault code then go back to VW, I have only done about 6000 since the recall, car has done 56000 total.

[doug1308]

Hi, this is my first post, but should prove informative regarding Emissions Recall and subsequent fix.
I bought a 2007 passat estate 2.0Tdi PD140 earlier this year, mechanically sound, but had a few parking brake, airbag and water coming in problems, so bought a 50k 2010 2.0tdi Cr140 estate. I found the new car a dream to drive but not as quick or as economical as my 2007 model, and the engine not as smooth. I did a check with Volkswagen and found it had been recalled and had the emissions fix.
I took the car to a tuning shop that I knew in the Perth area for advice. They were able to remap my car, but they found that yes, the VW fix map could not be altered as has been stated on the forum here. But the were able to remove the software and install a previous version and then upgrade that with new software.
The new upgrade is around the 170 bhp, and they reckon that the old VW emissions fix had tamed the engine to around 100bhp,(they have driven hundreds of cars). The engine is a lot quieter, better low down torque, and consumption went from low 30s to about 40 around town. There is a very slight turbo delay, but not too noticeable. Any reports on the forums about the VW emissions recall have reported increased engine noise, increased fuel consumption, and a drop in power.
Any questions, I will try and answer them on here, or PM me. i am not a young petrolhead, but a retired mechanic.

[Crasher]

I had a 1.6 CR TDI A3 cabrio in today and it was awful to drive and diesel knocked, with no codes. I could not find a service book or sticker in the boot but looking at the identification info in the engine section on VCDS I could see it had been recall flashed in March. The only symptom I could find was that I had just jumped out of a Golf 5 TDI into this and noticed the accelerator pedal felt dull and restrictive so we fitted a new pedal and power was restored so it proves that you can have a faulty pedal and it not come up as a code and the live data was the same with the new pedal as with the old. It still knocks though, needs a decent remap to get rid of that.