I bought a 10 plate VW Mk6 Golf Estate a few months ago and its been great, until the past couple of weeks.
I don’t drive it much, but the missus say’s it randomly idles a bit rough.
Then last week DPF light comes on dash, I do the “spirited drive” thing and all seems well. Two days later and the light comes on again and smoke comes out of bonnet. RAC man called, who tells us to get to garage and get it sorted. Man at garage can’t find any faults, all soot levels in DPF correct and sensors reading correctly. He does a Regen anyway just in case, strangely no error codes on diagnostics. Car fine for another week then does the judder y drive , smoke out of bonnet thing again. Aaarrrggggh!
Any advice would be appreciated, if there’s any VW mechanics on here.
Cheers 🙂

Get it deleted and remapped, then it will go like stink and not just stink.

Smoke shouldn’t be coming out of the bonnet.

One thing to check is that the pipe to the egr isn’t cracked they usually do it on the corrugated section.

its only a 1.6 TDI on 35,000 miles, so don’t know if its worth remapping. Will remapping make much difference to power/MPG really? Will check egr pipe ( if I can find it, i’m not a mechanic, but ok on spanners ) don’t know what colour smoke was cos missus was driving it. If the pipe was cracked would it not smoke all the time?
Sorry bout all the questions, but I’m abit reluctant to take it to garage again

I would think twice about removing a DPF and remapping a VAG 1.6TDI. It’s only a matter of time before MOT tests become more stringent and start actually check that the DPF is present. I’ve also read horror stories on German VW forums of remapped 1.6TDIs breaking con-rods as they can’t handle the extra power output (and these were not silly remaps ie 50% more output).

In fact, the 1.6TDI is not proving to be a great engine, just like the VAG 2.0TDI – they’re both suffering broken con-rods, cracked heads and failing EGR systems…..

Remapping a car will highlight any current faults so if you do have a cracked pipe or faulty engine it will only get worse with a remap.

“It’s only a matter of time before MOT tests become more stringent and start actually check that the DPF is present”

and how willthey do that ?

the same way they check my non existant cat is there ?

I’m fairly confident even Halfords mechanics can spot a missing cat if they are asked to.

various mot testers have not managed – including my latest mot last tuesday . failed on a balljoint , ARBs , corroded brake pipe and steering UJ play

but no mention of the lack of cat.

so obviously not looking “that” hard if its so easy a halfords mechanic can spot it …..

but no mention of the lack of cat.

And I assume no O2 sensor?

I’m guessing your vehicle either doesn’t need an emissions test or is it old enough to only need to meet the 3.5% test?

Marko

spanners ) don’t know what colour smoke was cos missus was driving it. If the pipe was cracked would it not smoke all the time?

If it was a female driver, was it clutch smoke???

(sorry, couldn’t resist :D)

2006 dw8 engined peugeot.

no o2 sensor.

no turbo

minimal ECU input into the running.

simple cars have their place in being utilitarian.

there are work arounds for most vehicles though. ive seen a few fake cats on motors which just have a staight pipe through so for MOTs it looks all good (for a diesel) petrols will “generally” fail an mot on emissions without one – but then petrol cats are useful.

dw8 engined peugeot.

Diesel then – I assumed petrol. No cat is ever a problem on a diesel, as (at present) it’s only the opacity of the soot that is measured at the MOT.

Back on topic . . .

OP
Ignore any talk of getting it remapped and junking the DPF. Get the problem fixed.

First what’s your location?
Second did you take it to a specialist?
Third; any idea of what diagnostic tool was used?

Marko

If there are no error codes being logged then I’d look at the induction pipe work first. I’d be very suprised if an electronic fault was one that wouldn’t register in some way.

Is there any oil leaking out of the induction pipework? – ie the pipes that run from the air filter through to the cylinder head. It may be pretty long as its turbo charged and it may have an intercooler.

Are all the pipes seated correctly / clamped in place.

If the only journeys the car does are short, start stop drives then it could be gummed up from running too rich.

Check the air filter too. Give it a bang out to clear it.

When was it last serviced? Were all the filters changed during the service? Is there any possibility that some water has got into the fuel?

My Touran had a very sooted up EGR valve and a couple of small holes in the induction pipework. Would be very smokey and run rough. Swapped over the damaged hoses and things improved greatly. I actually deleted the EGR valve rather than clean it it ran smooth and smoke free.

Left field suggestion but check the intercooler pipes (although not sure how they would cause the smoke some of the other symptoms sound not dissimilar to the split ic pipe I had a few years back)

If something was split causing smoke, it should do it all the time, or at least consistently.

I’d bemore inclined to think the juddering is a regen happening (some cars can judder during it, but havn’t got a clue about VWs), and the smoke is oil burning of the exhaust system. However that’s total speculation without seeing the vehicle.
Plus the only experience I have with VW 1.6 diesels, is I got a company one classed as beyond economical repair due to needing a new turbo.

Thanks for all your replies, its given me a few things to check.

Marco, I live in Halifax, I took it to the local garage, not a VW specialist but competent and trusted mechanic who knows his way round diesels. I have know idea what diagnostic tool he used, would it make a difference?

Tar muchly 🙂

I have know idea what diagnostic tool he used, would it make a difference?

It can do. A generic scanner may not display as much data as a something like VCDS or Autologic. All though to be fair most scanner manufacturers have VAG group cars nailed.

Where no fault codes are displayed, it then becomes a question of a test drive whilst looking at the live data – this is where a good scan tool is needed and more importantly a good technician who can interpret the live data.

However if it was me and I had no fault codes my next test would be a smoke test to check for air leaks. Find a garage with one of these (or similar):

Alternatively give Autologic a ring and ask them who has the VAG group software in your area. Any garage that has Autologic for VW should know what they are doing as the tool cost an arm and a leg.

Hth
Marko

Dont let your garage try and tell you solus works for all. It doesnt

My 12 quid scanner picks up citroen and renault faults better than my mates up to date 3000 quid solus system….

Vehicle specific kit is best though.

Are you sure its not something obvious like the rad cap / expansion bottle opening and letting out steam? Have you checked your fluid levels to see if you arae loosing any , or has the car overheated at all?