- Jan 24, 2020
- Reaction score
Dont listen to these that are saying you don’t use it enough that’s why it’s blocked as thats got nothing to do with it, these are probably the guys that drive petrols.
It’s more down to how you drive it and not how far you drive it. If you look in the handbook it tells you that if the dpf light comes on then you have to drive for as long as possible above 2000 rpm until the light goes off. If you go by that theory most of the time when the dpf light isn’t on then you will stop it from coming on as the higher rpm burns the soot off. However if you’re constantly doing 30 or 40mph in 5th or 6th gear then the dpf is going to have more chance to block up so then it’s your fault.
Having said that if nothing is faulty then the car should regenerate at some point on its own if the engine is running for long enough, for instance maybe on your weekend runs.
I have a 2010 170 tdi and do 5000 miles a year at most and my dpf light has never come on.
It sounds to me like something is faulty though if vcds says it has 0 ash as that’s pretty much impossible if the light is coming on and your car has over 100000 miles.
You don’t want to get the dpf cleaned until the fault has been fixed or until it’s been proven that nothing is at fault and it’s because of your driving style otherwise it will just fill up again.
Having the glow plugs checked is a good starting point as cars don’t usually regenerate with faulty glow plugs but you would have had an emissions light on the dash anyway if a glow plug was faulty.
There are lots of other things too that can affect it such as dpf pressure sensors, split hoses/pipes, too much oil or wrong oil so you need a garage that can check all these things before you get the dpf cleaned, cleaning the dpf should be the last thing you do.
I've just had it in with a Diesel specialist garage and they've run tests on the sensors and plugged it in to VAGCOM. No evidence of split hoses/pipes and everything looks ok.
The ash level is showing as 0.00 and he reckons a previous owner has manually reset that because the DPF looks to be the original so like you say, it can't be at 0.00.
He has recommended the next step is to fully clean the DPF of Soot/Ash so I've booked that in for Friday. Fingers crossed it is just full of ash and needs a good clean!
It's not ideal because I don't know for sure that it's ash causing the problem but it seems the most likely contender given the strange 0 reading in vcds.