Feeling the Regen while driving

Does anyone else feel their TDI regenerating on the highway? I've noticed the feeling of driving into a headwind at times, and even what feels like the tranny slipping a little. It seems to be most noticeable when cruising at 75-80 mph. Is this the "passive" regen at work?

Nope. Only way I can tell is when I stop at lights, and it's idling at 900 rpm.

I have a PF03 installed and watch codes which reveal the ECU status codes related to regen.

the only time I can detect a difference, is when it goes into an NOX cat regen. and only under some conditions.

(moderate speed and light throttle)

http://www.natef.org/NATEF/media/NATEFMedia/VW Files/2-0-TDI-SSP.pdf

see page 72

Passive regeneration is just that, passive.

no engine parameter modification is called for, just the result of operation, at say, highway speeds or up hills. any time the catalyst temperature is high enough, and there is enough O2 in the exhaust, the DPF will convert captured soot into CO2.

It must be the NOX cat regen that I occasionally feel then.

BTW - Incredible teaching manual - thx for sharing

Just sharing what was earlier shared on these pages.

Mark SF said:

Nope. Only way I can tell is when I stop at lights, and it's idling at 900 rpm.

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My normal idle is 800

My RE-GEN is at 1,000

mine runs like a washer full of bricks when its in a cycle.

While in regen, my front tires like to chirp easier when I floor it from a stop.

for the more anal reader, I ran a log last month including a DPF regeneration, and caught some time stopped in traffic during the regen.

idle speed 943 during the regen

idle speed 828 after starting, before regen

and idle seems to be 851 for a while after the regen.

Happy to share the file if anyone really cares.

My car almost feels like it will have a single missfire or a single hiccup while driving before regens.. It will do it a few times while it is “thinking” about it.. Then the cat temps normally start to go up shortly after.. If I use an fuel additive I feel it less.. I don't know if it is normal but I have deemed it as..

I certainly notice my 2013 Jetta regenning on the highway. Sometimes its completely muted and I don't notice it's doing a regen until I look at my scangauge and see my DPF temps at 1,200F. Then there are times when it stutters, or lightly jerks and I know exactly what it's doing when I feel it.

Yeah, I can feel when my car is going through a regen, I can feel the car buck/surge a few times before it clears up usually.

With mine the only indication I get is a lower than normal MPG reading off the dash display. My TDI normally idles at 900rpm's - it increases to around 950 during a regen. When I first got the car I was surprised the first time I shut it off and interrupted a regen cycle - the fans were on very low speed after shutting it off. That is when I discovered it might not have been the best choice for my driving needs. My most often 'commute' is to-from the golf course (I'm retired) which is 2 miles of in-city and 5 miles of highway driving. VW did not cover this in any of the literature I read. Edmunds.com didn't cover this aspect of car buying either. I should have delved into the TDI further prior to buying this car but I'm not at all unhappy with it - in three years and 19000 miles I haven't had a single problem with the car.

I have a Scangauge II installed now and can see the regen coming by the increased exhaust gases. Things get very hot during a regen. This cannot be good for long term longevity IMO. The Malone 2.0 tune with RawTek exhaust replacement should cure that. Just gotta get to June 28th to see where we are with these cars. One more week eh?

spaceCadet said:

mine runs like a washer full of bricks when its in a cycle.

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I gather your TDI may be due for some maintenance. Regeneration, what in the world will VW engineers come up with next. Must admit I liked the idea of an NOx trap over a silly AdBlue tank.

A 2014 Passat owner I spoke to on the street thought my 2009 was ALH-like as it has no AdBlue, which is a pretty cool thing. He was wrong but when I tried explaining Dieselgate he still thought himself to be in a bad situation.

Then I thought to myself why us Volkswagen owners are different. We talk about regens, DPFs, HPFPs, AdBlue, etc. Who else in the car world even know what these things mean.

An elderly man at an auto service place nearing retirement where I took the wife's car in for an oil change told me I knew more about diesels than he ever cared to know. That's when it struck me, just drive the darned thing and stop worrying, sure not easy I know.

I certainly feel mine regen. It's not a "limp mode" feeling but as you say, it feels like a headwind. Occasionally I get little spurts or power surges that make then engine react a little strange.
Just had the 40k mile service done, so everything is up to date.

mydecember1985 said:

I certainly feel mine regen. It's not a "limp mode" feeling but as you say, it feels like a headwind. Occasionally I get little spurts or power surges that make then engine react a little strange.

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Same here.

My car feels like it has more pep during a regen. Idling at a stop light during regen, my car shakes a little bit.

mydecember1985 said:

I certainly feel mine regen. It's not a "limp mode" feeling but as you say, it feels like a headwind. Occasionally I get little spurts or power surges that make then engine react a little strange.
Just had the 40k mile service done, so everything is up to date.

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Exact same for me.... I also have the PF03 and I can "see" based on the codes when it's doing a regen and what kind, but I can almost always "feel" those little surges before I visually confirm it's in a regen.

Mine got a new fuel system a year ago due to lift pump corrosion/contamination (not an actual HPFP failure, but they basically handed it the same and replaced all of the same stuff, including the HPFP) and I noticed it happening before that, and it was no different after.

FVWVWF said:

Same here.

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Same for me, rough idle / stumble once or twice if in city traffic

The only way I know regen is happening while driving is because I monitor various temps with Torque. I see that the cat and another are running about 1000degreesF. Otherwise when I stop, the fan is running to cool everything down.

As someone mentioned, my trip mpg might be down a bit but often that is hard to notice as that can vary on weather, number of stops, length of trip, etc.

Most definitely feel mine. There seems to be a few different regens.

1000 rpm idle. Much better throttle response and torque. Feels like it has a tune.

Sometimes its like that guy up there said, a washer full of bricks.

Sometimes its kinda doggy feeling.

It most certainly isn't transparent in any case.

Assuming all are cars are the same, your car does not have some other issue,
You have some great sensitive seat of the pants senses. No I can not tell I am
having a regeneration during freeway sustained driving. You should not feel
loss of power. That is not normal.

I have a Scangauge II, monitor my EGT pre Turbo (the highest one). While
driving NO REGEN, normal freeway cruise EGT is about 600F to 900F
depending on road, flat, going up hill, accelerating, etc. These are ball park
numbers. However during REGEN you see sustained high EGT reading
well over 1100F to more like e 1200F or higher.

You will see at idle EGT in the 400F to 500F normally. If stopped at idle,
during Regen EGT will still be much higher 900-1100F. As mentioned
the idle is higher.

All the REGEN does is inject extra fuel later to cause the fuel to burn rich
and in the exhaust, raising the EGT. That high Temp is used by the DPF to
REGEN the soot into ash and water. If you are paying attention to your
current MPG you will go down during REGEN; you are burning more fuel.

If you can sense a REGENS while driving that is pretty good. However if you
feel it is down on power significantly, that is not normal.

On the highway, it's generally not really noticeable. In town, stop and go, oh yes definitely. And I've seen EGT's get up to 1500F, assuming my xgauge was set correctly.

ive watched a few regens happen with my vcds ,most it doesn't affect the drive , but around town it sounds like the air filter is loose/missing,it has that sort of engine sound too it. the last one I had was Wednesday and Thursday,it started just before my journey end, I could hear it,when I stopped the car ,no fan running ,next morning I had a short trip it started again and it stopped when I got home ,then that afternoon it started again around town , so I drove it for 3-4 miles on country roads and it then finished the regen, typical temps are around 700-800, never seen any higher than that,i do use a combination of a cetain booster and a fuel conditioner /pump lubricant , that's probably the reason temps are lower!.

Your temps are probably in Celsius.

bhazard,your right I forgot that there are differences in models and countries in terms of what they read out. all my dpf readings are in grams,yours are in mls.

Definitely can tell when regen is running. Better yet I'm starting to notice the difference between LNT and DPF regens. Either case light load between about 35 and 45 I can consistently make the car "hiccup". Sometimes you get a little jerk when regen starts. DPF regens seem to have bigger effect on MPG than LNT regens.

Jason

Where does the fuel come in to burn the soot off the DPF? Is it from the injectors in the combustion chamber? Or is it after the turbo which I guess would mean it would have its own fuel supply? When I read about temperatures going into 4 digits I have a visual that the oil is being cooked significantly if in fact the source of the extra fuel comes from the injectors.

Injectors, late in the combustion cycle IIRC.

When regenration occurs while driving, say city driving where the cooling is not ideal, does the temperature gauge show an increase in temperature? If there is no increase then is it safe to say that all the 1100F-1400F heat is downstream from the combustion chamber?