TDI Recall

[Russ59]

Hey all just thought i would let you know the outcome

Well 2 months after putting the car in for repairs i finally got the invoice for the work done.

Direct quote from the invoice

"traced the problem to the diesel particulate filter and exhaust pressure sensor, Diesel Particulate Filter was replaced and cleaned, fault codes cleared and road tested"

all in all
1) I was without the car for 1 week without a loaner, after being told the car would be ready after 1-2 days.
2) wasnt given any invoice or workshop notes when i picked up the car as "they werent ready" had to chase up the invoice 3 times on the phone, got annoyed and picked it up in person.
3) wasnt provided with the print out of fault codes as i asked for...

Definitely not going back to Denlo for any service or purchase of my next car....

now would i get a survey thing from VW for warranty work?

Hey mate,

Just wondering if I might ask, what was the problem you were experiencing with your car that warranted the replacement of the DPF ? Was it running really rough or what ? Just interested because I've been having some issues with mine during the regeneration cycle and am starting to wonder if it may have something to do with a sensor for the DPF. The annoying part is that when I get it to the dealer and they run a diagnostics check on it apparently there are no error codes registered, but at times (like just this morning again) it has started to do what I believe to be a regen cycle, idle goes up to 1000 rpm, I generally pull over somewhere and wait for it to finish (idle drops back to normal 800 rpm) and away we go. This morning it dropped back to normal idle speed and as soon as I went to take off and gave it a few revs it started again and was running very rough. When I got it back home it had a very hot burning smell coming from under the car ( which I assume was due to the high heat associated with the regen process) I rang my service dept. and they say it doesn't sound normal (as usual). Guess I'll be taking it for another visit to the dealer and see if any errors have registered this time. Just about to take it for a run now and see if it's settled down or still playing up. Sorry to hijack the thread, but it is associated to a degree.


Russ

[adrian112]

Hey mate,

Just wondering if I might ask, what was the problem you were experiencing with your car that warranted the replacement of the DPF ? Was it running really rough or what ? Just interested because I've been having some issues with mine during the regeneration cycle and am starting to wonder if it may have something to do with a sensor for the DPF. The annoying part is that when I get it to the dealer and they run a diagnostics check on it apparently there are no error codes registered, but at times (like just this morning again) it has started to do what I believe to be a regen cycle, idle goes up to 1000 rpm, I generally pull over somewhere and wait for it to finish (idle drops back to normal 800 rpm) and away we go. This morning it dropped back to normal idle speed and as soon as I went to take off and gave it a few revs it started again and was running very rough. When I got it back home it had a very hot burning smell coming from under the car ( which I assume was due to the high heat associated with the regen process) I rang my service dept. and they say it doesn't sound normal (as usual). Guess I'll be taking it for another visit to the dealer and see if any errors have registered this time. Just about to take it for a run now and see if it's settled down or still playing up. Sorry to hijack the thread, but it is associated to a degree.


Russ

Hey Russ,

I didnt notice anything really rough or anything but the engine fault triggered as i was merging onto a motorway. The engine was reving out as normal then it seemed as though a knock happened in the engine and the car was in limp home mode.

I do notice that the car acts like how you mentioned when im in alot of stop start traffic though.

[Russ59]

Hey Russ,

I didnt notice anything really rough or anything but the engine fault triggered as i was merging onto a motorway. The engine was reving out as normal then it seemed as though a knock happened in the engine and the car was in limp home mode.

I do notice that the car acts like how you mentioned when im in alot of stop start traffic though.

Hi Adrian,

Thanks for that, I haven't experienced that with mine and hopefully I won't, but I have had a lot of experience with the regeneration cycle happening and for some reason mine always seem to be more predominent when the car is cold which makes it twice as bad

I took it for a run about 150 k's return trip today and all was good again, running like clockwork. It must have been doing an extra long regen this time around because it was running like crap on and off for nearly 15 minutes. It's a PITA though when it does it when you're in stop start traffic and from previous experience can be dangerous as well. As soon as feel it starting to surge and I see the idle is up at 1000 rpm I know it's doing a regen and I always pull over somewhere now and let it do its' thing, I'll just have to be prepared next time now that I know that it might want to have another crack at it if it didn't complete the cycle on the first go, or maybe the DPF was extra dirty this time around.

Russ

[benough]

Russ

I am pretty sure you know how the regen works. The engine injects fuel during the exhaust cycle so it goes uncombusted through to the DPF where it hits the hot grid and burns heating it up, burning off the soot etc.

When mine had a hissy fit about the DPF my dealer pretty much told me to drive it harder!

I can't see why sitting idle would be a good idea during the regen cycle. Don't use the brake, use the accelerator!

[Russ59]

Russ

I am pretty sure you know how the regen works. The engine injects fuel during the exhaust cycle so it goes uncombusted through to the DPF where it hits the hot grid and burns heating it up, burning off the soot etc.

When mine had a hissy fit about the DPF my dealer pretty much told me to drive it harder!

I can't see why sitting idle would be a good idea during the regen cycle. Don't use the brake, use the accelerator!

That's why I took it for a good run to make sure it had finished, It was a bit hard to fang it around town there were cops everywhere I almost got nabbed by an unmarked crumbledore hiding in the scrub this morning, luckily I spotted it before I planted the foot in 2nd gear. Basically with mine, as I said, it tends to want to do it when it's cold and it makes it near impossible at times to stop start in traffic without stalling, it really is that bad when it starts the regen process when the engine hasn't reached operating temperature

Russ

[gregozedobe]

I might be wrong, but I thought that you were supposed to drive at a steady speed (2nd, 3rd or 4th is best) with the rpms between 2,000 and 3,000 to allow the ECU to do a proper regen. If you allow it to idle the revs are too low, if you fang it the revs are varying and you are producing more soot that needs to be burnt off too.

Doesn't the MFD tell you to drive at 2,000 rpm or something ?

I've never noticed a regen on my 2.5 TDI Transporter (which does have a DPF), but I do nearly all gentle (legal) highway driving.

[Russ59]

I might be wrong, but I thought that you were supposed to drive at a steady speed (2nd, 3rd or 4th is best) with the rpms between 2,000 and 3,000 to allow the ECU to do a proper regen. If you allow it to idle the revs are too low, if you fang it the revs are varying and you are producing more soot that needs to be burnt off too.

Doesn't the MFD tell you to drive at 2,000 rpm or something ?

I've never noticed a regen on my 2.5 TDI Transporter (which does have a DPF), but I do nearly all gentle (legal) highway driving.

That could be a PITA though Greg if the car decides it's going to take nearly 15 mins to finish it's regen cycle. It sounds as though you've been quite fortunate with doing mainly highway driving and haven't had to experience the dreaded regen cycle in stop start traffic. It doesn't even give you any warning when it decides to go into the regen cycle, the only way I have been able to determine it was happening was when the idle went up to 1000 rpm, and it generally starts to surge and run very unpredictably (in a nasty way) I have found that it helps to just take it for a good drive and let it do its' thing until it's happy and runs normal again. Until the next time


Russ

[gregozedobe]

I deliberately didn't give an opinion on whether it would be easy (or even possible if you are in heavy traffic) to run the engine at steady revs to help the regen, just that is what I thought VW say you are supposed to do

From what I've read on the Briskoda site the 125Kw 4 cyl TDI PD engine is by far the worst VW engine for regen problems, but once the (often) faulty exhaust sensor has been replaced and the ECU has been re-programmed (IIRC there is a "campaign" to do all of them) there are a lot less DPF problems.

IMHO they are just not suited to someone who does lots of driving in heavy (stop-start) driving, and a heavy right foot seems to make it worse.

I think VCDS can give you stats on the current "fill" level of the DPF, which might give you warning a regen is imminent, but that isn't really the way I'd like to be driving my vehicle.

Update: I just had a look in my owner's manual (the "Tips and Maintenance" booklet) and it says the following (in summary):

..... The soot particles are collected in the filter and then burnt off at regular intervals. To assist in this process, we recommend that you try to avoid making only short journeys.

When the diesel particulate warning lamp lights up, the DPF has become saturated with soot as a resut of driving short distances. To clean the DPF, drive the vehicle at a constant speed of at least 60km/h for at least 15 minutes. The DPF cleans itself most efficiently when the revs are approximately 2000 rpm in 4th or 5th gear. This will increase the temperature and burn off the soot in the filter.

In addition, a message could be shown in the display to provide information or to request you to perform certain tasks.

.....it is essential that you adjust your speed to suit the weather, road, off-road and traffic conditions. You should not allow the recommendation given by the warning lamp to let you ignore traffic regulations.

So it sounds like the DPF warning lamp (the little yellow rectangle full of dots) should light up when the DPF is doing its regen thing. And a DPF regen is no excuse for speeding !

[Russ59]

I deliberately didn't give an opinion on whether it would be easy (or even possible if you are in heavy traffic) to run the engine at steady revs to help the regen, just that is what I thought VW say you are supposed to do

From what I've read on the Briskoda site the 125Kw 4 cyl TDI PD engine is by far the worst VW engine for regen problems, but once the (often) faulty exhaust sensor has been replaced and the ECU has been re-programmed (IIRC there is a "campaign" to do all of them) there are a lot less DPF problems.

IMHO they are just not suited to someone who does lots of driving in heavy (stop-start) driving, and a heavy right foot seems to make it worse.

I think VCDS can give you stats on the current "fill" level of the DPF, which might give you warning a regen is imminent, but that isn't really the way I'd like to be driving my vehicle.

I wasn't implying that you were saying it would be easy or not mate, I was just talking from my own personal experience with the regen cycle.

I don't do a great deal of stop start driving in traffic with mine but it's still a pain when it starts its' cycle. I have had it into the VW service dept. already and complained to them about what it does but because it doesn't register any error codes they wont do anything to it. I suppose I'll just have to live with it for now unless it chucks a code sometime and then they might do something to rectify it, I still don't think it should do what it does because it really does make it very difficult to drive whilst it's going through the cycle.

Russ

[gregozedobe]

It might be worth asking your dealer about the "26E6" campaign if you haven't had it done to your car already. It is supposed to improve things a lot - replaces the dodgy exhaust pressure sensor and remaps the ECU too.

If they don't know anything about it maybe harass VWA, as it has been on the go in the UK for months now (Aug 2008 ).

VWA can be very slow with these campaigns - in the UK they were replacing the batch of faulty oil coolers in R5 (transporter) motors for 6 months or more before they finally got off their rear ends and started fixing them in Oz (and of course in the meantime mine had carked, causing me no end of problems).