DPF Rigmarole

dufresne2011

Hello All,

 

I badly need some advice. I have a vw golf 2009 2.0 tdi. About 6 months ago, two error dashboard lights started popping up intermittently – check engine light and glow plug light – brought her to a mechanic who said it was a DPF sensor. He changed the sensor and the lights popped back up a day later. He then changed the sensor again (on the off-chance that sensor was faulty) and same thing happened. Then he said the error was DPF related. As a next step, he flushed out the DPF and lo and behold, a couple of days later, lights came back. He was scratching his head. I should say that although we mostly use the car for small journeys we do a long journey about once a month but she doesn’t seem to be doing regens. It could be that the DPF is banjaxed and needs to be replaced which will cost a small fortune. I’ve done some research and gone to another mechanic to discuss remapping - quoted €450 for remapping (removal) of DPF and EGR Valve. My head is melted from reading the pros and cons of this (which I won’t go into here). My questions is, what would you do? If lights are there, car won’t pass the NCT so I should do something (as opposed to just ignoring it and carrying on driving). My mechanic and I are sick of looking at each other (I’ve spent close to €600 on this already) and if I bring it to a VW dealer mechanic I’ll come out with a quote larger than the value of the car.

 

We badly need the car as we are very remote. Based in Cork. I should also say that the car isn’t losing power and dashboard error lights aren’t always up. Any advice?

 

I’d very much appreciate any advice as am pulling what's left of my hair out.

User1998

Only option now is to remove the DPF or replace it.

The only cons to a DPF removal are the environmental impacts.

Edit: Well, there are probably other options, but you’ll just be throwing parts and money at it.

Birka

It sounds like your mechanic is out of his depth, a bit too easily too. He's done a lot of work at your expense and left you back where you started.

Try and find a VW independent specialist and get the fault codes read. Given the approach that your mechanic took, it seems to me that he didn't (or wasn't able to) read the codes properly. An VW specialist will be able to read more detailed error info. Without knowing what the issue is, going ahead with any fixes might well just cost you more money and not get the car fixed.

dufresne2011

https://www.boards.ie/discussion/comment/121332324#Comment_121332324

Thanks Birka. I don't blame the mechanic. He's a good mechanic, I'm just looking for options really. I'll do a bit of research on a VW independent specialist but I'm just conscious of the potential cost involved.

realdanbreen

That whole regen/ DPF thing would wreck your head,I had the same thing with a vauxhall insignia. For the NCT I covered the warning light ,it sailed through then I swiftly traded it in.

teediddlyeye

Bring it to a different mechanic, most DPF issues are usually a small underlying issue that prevents a regen from running. Often the cost of which would be cheaper than a remap to repair correctly.

I would double check your mechanic has checked the wiring on the sensor, I had a similar issue with a passat in the garage, an indy had fired a new sensor into it and the customer was freaking out at the cost of either a new DPF or delete. Turned out a rat had chewed the sensor wiring under the battery! Cost to repair was some crimp connectors!

Personally would advise against deleting it. It can make future diagnostics an absolute headache and may be a potential NCT fail in future.

They rarely actually fail, mostly poor diagnostics.

10-10-20

Have a look on here - this guy is very good a providing tips on regen and DPF issues:

https://www.youtube.com/%40ORileysAutos/videos

Kimbot

Mostly small journeys is whats killing you i'd say, I would bring it out on the moterway and low gear high revs and blast it out a bit and see how you get on.

Sparky2009

Great responses

Padre_Pio

I would question the DPF flush and whether it was even done right.

You could also open the DPF and get it cleaned properly with a power washer and ultrasonic cleaner.

Maybe under €200 for that job.

In my case the mechanic never refilled the PAT fluid on my Volvo, so the regen didn't work properly. I needed to get the DPF properly cleaned to bring the car out of limp mode.

XsApollo

What happens when the check engine light comes on?

does it go into limo mode or just goes away again after a few days?

what codes were actually read?

If the light isn’t affecting the car, then Run some JLM Diesel extreme clean for a tank, take it on a long drive on the motorway , stay in 5th if you have a 6speed, and then redex diesel for a couple of more tanks.

Mt A6 used to throw up a code for DPF bank 1 above threshold intermittently over a good few months.

anytime I filled up in the EMO fuel place on my commute which Id do when I was stuck .

I swear a few days later light would come on.

i ran some of that JML diesel and redex diesel for a few weeks and I haven’t seen the light in a long while, and my car definitely runs better after it.

I know some people think they are snake oil, but it might help and might save you trying diagnose the issue you are having.

dufresne2011

https://www.boards.ie/discussion/comment/121333347#Comment_121333347

Thanks for the advice XsApollo. The lights are intermittent. Some days they're not there at all, others there's one or more of them. The car has never gone into limp mode. It runs fine other than this.

JML diesel and redex diesel are new to me. I'll give them a go.