Very frequent regeneration

Regen cycles will always be necessary no matter what. Some types of driving though require more often regens to burn off the soot to ash. Short tripping is one of these things. You don't drive far enough or long enough for them to happen and then the soot builds up, sometimes to the point of having to go to the dealer. If you interrupt them they will restart as soon as they can when you resume driving. It is imperative that you find some way to drive and let them finish if you are short tripping all the time. After the fix they should happen every 2oo miles or so. There are a few OBDII gauges you can get to monitor them and see what is happening so you can decide what to do. Vagdpf is one and works on android phones with an OBDII dongle. Fairly cheap too.

A regen will always happen eventually (i.e, "be necessary") even if you drive 1000 miles nonstop with engine at full operating temperature, e.g., at 65 or 70. As noted earlier in this thread the regens will trigger on either a) soot load, OR b) absolute number of miles driven since last regen, which IIRC is about 250 miles or so.

If you want to regen as infrequently as possible try for condition b) and drive at full operating temp as much as possible or as long a distance as possible.

I pay no attention to regens - they just happen and I motor on.

IIRC a pressure delta can also start one.

Temps? like coolant temps? the ECU can start a regen at any coolant temp, it's the EGT temps that factor into when the DFP "lights off" and accomplishes an active regen. On my Gen 1 jetta a couple times she went into a active regen within 5 min of idling through stop and go traffic on a cold engine.

On our '15 Passat, I have noticed a few times the coolant temp gauge moved very fast on a cold morning, sure enough it was doing an active regen. Oil temps also climbed much faster for the conditions.

The biggest thing I noticed was the duration of regens, steady state highway speeds, it takes almost 10-15 min for a regen to complete. If a regen is interrupted it may not start another active regen until loading hits a threshold again.

Drives of +30 miles each start seems the best way to avoid stopping regns.

The best way is to monitor them so you know when they are happening and can then take action if you choose to. They usually start at around 24 grams of soot and complete down around 5 grams. These are close estimates not actual hard and fast numbers.

2013 Passat TDI auto 127K I have read a number of post regarding the regen frequency topic. I do understand that we are most likely driving the car locally and not allowing the regen to complete. Here is what is perplexing me. Last year we drove from Central Illinois to Charlotte North Carolina. that is 725 miles one way, only stopping for fuel breaks. Then back 3 days later. 90% of the drive had the REGEN process working while driving. I took our car in for service before the warranty was up, and the VW dealership said nothing was wrong with the regen process. Normal driving is just typical running into town 3-4 times a week. The regen process is still VERY frequent, like almost every other time we use the vehicle. I do not trust our local VW dealership and my local mechanic isn't to keen on working on my car. What possibly could going on or what should I be looking for?

There is a pressure sensor below the engine cover, top of the engine, passenger side, with two small rubber hoses that come out of it that go to the dpf. That sensor could be bad, or there could be an obstruction (carbon) in the hose, that might be affecting regen frequency. I would start by pulling the hoses, blowing them out, and if they are clear replacing that sensor. If the problem persists, consider tuning the car with a Kerma tune. I did that 15 months ago after being plagued with excessive regens for a long time and now I go 400-500 miles between regens. I also had to the "200 mile to no start" adblue error code pop up and that is when I threw in the towel and tuned the car. I did replace the sensor as well. Its not that expensive.

Most likely a scan should show the sensor a problem. Thanks for the feedback. Any idea what the part # is for that sensor?

Just hit 210k miles on my 2015. Last 10k the regens are becoming quite frequent at every 80mi - prior to this they were about every 200-300mi. No engine codes yet. Mileage is going down fast. Might the differential pressure be triggering this and is the filter not working as efficiently? Any insights or experience would be appreciated.

I added a Kerma tune over the summer. My regens went from every 200 mi to around every 475 mi. I'm happy with that.

Kalevi1Poeg said:

Just hit 210k miles on my 2015. Last 10k the regens are becoming quite frequent at every 80mi - prior to this they were about every 200-300mi. No engine codes yet. Mileage is going down fast. Might the differential pressure be triggering this and is the filter not working as efficiently? Any insights or experience would be appreciated.

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I think if the diff pressure is having any issues they usually fail with wildly incorrect data causing a CEL not a "scaling" skew causing a more frequent regens.

At least thats what happened when my CJAA sensor failed.

So you're stating you're at 210K miles on the first DFP? has VWoA ever replaced the DPF/DOC as part of phase 2 emissions work?

Thanks and will look into that.

Correct - 210k miles with no DPF changes. In the diesel world how often does the DPF need to be changed out?

Kalevi1Poeg said:

Correct - 210k miles with no DPF changes. In the diesel world how often does the DPF need to be changed out?

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Depends on the ash load and max ash allowed on the DPF.

Kalevi1Poeg said:

Correct - 210k miles with no DPF changes. In the diesel world how often does the DPF need to be changed out?

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IMO VW designed it to last the life of the car, sadly their definition of the "life of the car" is a bit different than yours.

I'd say you're on borrowed time with the DPF.

So a minimum you had phase 1 emissions recall done. Do you know if you got phase 2A?

There maybe a good chance VWoA might pick up the tab for emissions replacement due to phase 2B not being complete.

See here


and here

740GLE said:

IMO VW designed it to last the life of the car, sadly their definition of the "life of the car" is a bit different than yours.

I'd say you're on borrowed time with the DPF.

So a minimum you had phase 1 emissions recall done. Do you know if you got phase 2A?

There maybe a good chance VWoA might pick up the tab for emissions replacement due to phase 2B not being complete.

See here

Do DPF’s actually wear out?

I’ve always thought that DPF’s filter out soot (carbon particles), burn them off during regeneration, but inevitably accumulate ash, which can’t be removed during regen , culminating in a clogged DPF that must be replaced, or at least manually cleaned. But, I recently came across a video from...

forums.tdiclub.com

and here

Phase 2 fix

I've gone through this thread, lots of great info...thanks all! I do have a question, and hope someone has an answer. I own a 2015 Golf TDI SEL, purchased in 2017 with 4,000 miles and Phase 1 done. I have not had Phase 2 done yet. I now have 90,000 miles and never had any issues to date. This...

forums.tdiclub.com

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Thanks 740GLE - will check into both these links. I will let everybody as we go along.

this will save you some reading

Are you Sourth or North NH?

I've heard good things about Quirk in Manchester for warranty work such as this, I'm this close for asking for Phase 2B plus a TB job from them. I just had to add coolant to the Passat for the first time in say 30K.

i'm nearing just 90k and experiencing the more frequent regens... i ignored the phase 2 work.

if VWoA says "you had you're chance" and denies warranty work at some point, i wonder if going full delete makes more $ense than
paying out of pocket for DPF replacement.
anyone else contemplated, or even done this?

oh, and i'm running Kerma stage 1, fwiw

The only thing that might throw a monkey wrench is looking at the flash counter and picking up on the kerma flash. "You ECU has been modified, we don't care by who or how, go pound sand".

Granted we were malone tuned (and flash back to stock) before we got phase 2A and they said nothing of it.

Then you're cards are dealt for a DPF delete.