Omf - dpf regen light on - B7 Passat TDI

[wind]

9,000 km so far and so far no DPF light (or at least I have not noticed it coming on!). Then, I do a lot/most of my driving at highway speeds . . .

[Greg Roles]

Guys you will only EVER see a DPF light if the normal regens it does fail. These typically happen once a tank or so at first, and become more frequent as the remaining capacity of your DPF slowly drops. You are not notified of these, but may feel the car running a bit "odd" for about 10 mins. I didn't ever see one on the dash with the instructions till about 60,000kms, and even if it comes on, it's no major thing, it's just saying "OK you need to go for a proper drive till this light goes out" as the DPF is about 60% full - but still a long way from a problem.

Worry if the "lit - follow instructions" DPF regens fail and you end up at 80% with the coil light as well, and the car in limp mode - time to visit a dealer!

[cru22z]

AAARRRGGGG!!!!!
Rang the dealer today and was told they can't see me until 22/10. So I said what happens now the DPF light won't go off. Reply - just drive it normally. aarrrgg!!!! So OK I drove it normally. Went for another high revving freeway drive for 1/2 hour then on the way home the bloody coil and check engine light came on! went on limp mode coming up a hill...arrgg!!! lucky not many car around and was close to home. FAR OUT!!!!

also i only fill up using the closest BP near my place..could this be the fault of BP servo also?
Anyways regardless this car is screwed! This is the last diesel car I will ever buy. Im going back to good old V6 power petrol engine or Turbo petrol.

[Greg Roles]

Drop me a line mate 0407 544 727, you need Vag Com and some help!

[Transporter]

Or go to independent VW shop, it could still be cheaper than replacing the DPF sooner as a result of driving with the fault and blocking the DPF as a result, either now or even worst when the car is out of warranty. You can always ask VW dealer, if they would supply the part (I assume it's the sensor only) for free if needed? Spending $200-$300 now could save you $$$ later and a lot of time and arguing with the VW that they actually have caused the DPF to fail.


Or do nothing and wait for VW dealer, if you sell the car when the warranty runs out. Just make sure you keep the record of the conversation you had with your dealer, because driving the car when the fault is displayed for a long time invalidates your warranty.

[cru22z]

Called VW Roadside and then they sent nrma to check the
Issue. The scanned the car and found an error. But now the check engine light
is gone plus the dpf and coil light.
What you guys think?

[Greg Roles]

Mate at only 15000kms you need to get it to a dealer as planned, you simply should not be having problems unless you only do short city trips, and the car never has a chance to do a 40% "phantom" regen. NRMA cleared the code, yeah, but I reckon the blockage and thus problem remains. My vote is the differential pressure sensor that detects the DPF load.

Find a local Vag Com and force a regen at your leisure. In the very least scan channel 075 to see the % load of the DPF for yourself. If you hit 80% plus the car will stay in limp, as beyond this level the potential heat buildup from a regen has indeed burnt the odd truck to the ground in the USA. The limp mode prevents this, but you need to do something prior to getting to that much blocked.

I plan on buying another Vag Com cable from Tim at Dubaddiction next week, so if you want to grab the full version one, I'll buy it back off you when you are done with it at what you paid quite happily! Otherwise find someone nearby with one you can borrow! I've already got mine loaned out to a customer, otherwise I'd send you mine.

[cru22z]

Looks like the nrma guy deleted the fault.
Now Vw dealership won't be able to look at it until it comes up
again. So If it doesn't come up by this Monday ill see
an independent vw mech to check the car.

[Diesel_vert]

So I said what happens now the DPF light won't go off. Reply - just drive it normally. aarrrgg!!!! So OK I drove it normally. Went for another high revving freeway drive for 1/2 hour then on the way home the bloody coil and check engine light came on! went on limp mode coming up a hill...

If you haven't already, try to do it by the book:


Speed: at least 60 km/h, but keep the speed consistent

Engine speed: between 1800 - 2500 RPM

Gear: 4th or 5th (manual), sport mode (automatic)

Duration: at least 15 minutes


You may have to do this at night when there is less traffic.

also i only fill up using the closest BP near my place..could this be the fault of BP servo also?

Not unless the fuel is contaminated.

It's not out of the question, but it's not common.

Looks like the nrma guy deleted the fault.
Now Vw dealership won't be able to look at it until it comes up again.

Not every error is permanently stored. Some may disappear upon restarting the engine - even serious faults.

If a fault code shows up, you need to get the dealer to plug in the computer while it's still showing for them to acknowledge the problem. It doesn't matter if you don't get it repaired on the spot, you just need to start the ball rolling in regards to any warranty claim. You can then book the car in for a suitable date.

If there's no fault code, then there is precious little the dealer can do about it.

[cru22z]

Ok today I took car on freeway as per suggestion above.
I noticed the car won't regen anymore like it use to when I
Drive it hard on freeway. I also noticed there is not much power as it use to.
The cars auto start /stop also works even after highway driving.

Should I continue to drive the car or give it a break until I see the independent Vag com.

[Diesel_vert]

Ok today I took car on freeway as per suggestion above.
I noticed the car won't regen anymore like it use to when I
Drive it hard on freeway. I also noticed there is not much power as it use to.
The cars auto start /stop also works even after highway driving.

Should I continue to drive the car or give it a break until I see the independent Vag com.

If the glow plug (coil) light and/or check engine light is on or flashing, I would recommend you avoid driving the car if possible.

Otherwise, continue to drive it as per the instructions in the book.

[cru22z]

If the glow plug (coil) light and/or check engine light is on or flashing, I would recommend you avoid driving the car if possible.

Otherwise, continue to drive it as per the instructions in the book.

The lights has been cleared by the NRMA assist, so far I have not seen it again.

It seems to me that Diesel is steadily losing it's appeal as its traditional virtues of simplicity and reliability and low running costs (servicing repair etc) are being wiped out by new emissions technology. Diesel should be more cost effective and efficient, however if the car is forcing drivers to go on long drive just to Clear the DPF then I guess it's pointless.

[Diesel_vert]

The lights has been cleared by the NRMA assist, so far I have not seen it again.

It doesn't necessarily mean the problem is solved, so keep your wits about you.

It seems to me that Diesel is steadily losing it's appeal as its traditional virtues of simplicity and reliability and low running costs (servicing repair etc) are being wiped out by new emissions technology.

Old tech is simple and reliable... but it's also slow, breathless, noisy, polluting, less efficient, etc.

If you want power, torque, refinement, efficiency, and all that jazz, you need to up the level of tech - which adds complexity.

Which is not bad per se (just because it's complex doesn't it can't be reliable) but if the complexity isn't well managed, then reliability will take a dive.

Diesel should be more cost effective and efficient

No, it depends on whether your personal driving circumstances can make diesel more cost effective and efficient.

Many people buy hybrid or diesel cars without doing their research or without doing their sums properly.

For example, a person who does 30000 km annually will definitely be better off with diesel engine, whereas a person who only does 5000 km annually will definitely be better off with petrol engine.

If you lie between these two extremes, then it's time to get out Microsoft Excel and find out where you stand.

however if the car is forcing drivers to go on long drive just to Clear the DPF then I guess it's pointless.

It's a design philosophy that VW has chosen, which has its pros and cons.

Unfortunately, it just happens that you're experiencing those cons right now.

...

Having said all that, until you can get your car scanned, we don't know what the true problem is, and what the extent of that problem is. It may simply be a borked sensor, or may require replacing the DPF itself, or maybe the entire engine is stuffed! - it's all just speculation.

Like I said previously, as soon as the glow plug light and/or check engine light comes on, you need to drive straight to the dealer if practicable, don't turn your engine off when you get there and get them to plug in the computer then and there.

[cru22z]

Since the vw/nrma roadside guy cleared the dpf/glow plug/cel lights my have yet to hear
my car do a regen. In the last few days I have been on freeways on high rpm.
When I get to the end of freeway the start/stop kicks in.
Should I be worry? Do u guys get a regen on freeways and when u get to the end at the lights
It's still running say the trip on the freeway was like 1/2 hour.

I'm really worried! I know I have an appointment with a local vag com shop on Monday but my
Appt wit Vw is another week.
I just don't want to do more damage not knowing what's going on now.
From having the dpf light not go off even after 2 days of highway driving to clear it, to getting the cel light
and limp mode on the way home and the nrma guy cleared the error and car just went back to drivable again.

[entice]

Start stop should work at the end of a freeway.. that's what its supposed to do isnt it?

only stops working if the battery isnt in a condition where it can fulfil its requirements.

Well that's my simple understanding of it.

Wife's car has 7K Km's on it.
she mainly drives it, mostly in traffic. No DPF issues yet.
Use to own a 1.9 CDTi Astra (no DPF, tuned) and a s=twin Turbo Saab 93 (DPF, and tuned) - nil issues and both driven hard
then purchased a Subaru Diesel Outback (DPF and Tuned) and had several forced regens...
Passat seems to have less issues and less noticeable regens. Mind you, we also take it out for a run once a month or so... I watch the oil temps and not sure if they correlate to when a DPF purge is going on, but I watch them get to 110 degrees and it makes me warm and fuzzy, thinking that a regen is on.

I'd think you have an issue with a dud sensor.... but I'm no expert...