DoctorDawg
Veteran Member
Thanks for the pointer to the interesting reading, Varmint. Just thinking about this exhaust system makes my head hurt.
Awesome link and I think this points to what some people are referring to as a stutter or misfire. I think it's the NOx catalyst going into a regen cycle where the ASV and the exhaust valve are closing.VarmintSlayer said:Some interesting reading here.
http://www.chiptuners.org/forums/viewtopic.php?p=20440&sid=94ff7de418f345f43c53863d713454c5
Note the key phrases:VarmintSlayer said:Some interesting reading here.
http://www.chiptuners.org/forums/viewtopic.php?p=20440&sid=94ff7de418f345f43c53863d713454c5
I have read that when you turn off the engine the fans can "race" for up to 10 minutes. Therefore, I surmise that the re-gen takes about 10 minutes or less.Turbine Suburban said:So does anyone know how long a regen takes? Is it variable?
I'm not a mechanic by any stretch, but with nearly 40K on my 09 TDI, and based on a considerable amount of research along with real life experience, I'd offer these thoughts.Turbine Suburban said:So does anyone know how long a regen takes? Is it variable?
Actually I can tell if my car is regenerating by listening to the engine idling before I shut it off. Even before you shut off the engine, there is extra noise coming from under the hood and from what I can remember, some of it is from the fan.JSWTDI09 said:The *ONLY* time you hear the fans racing is when you happen to stop and turn off the engine while the re-gen process is still going on. Then the fans race to keep things cool under your hood. The DPF gets up to about 1200F (650C) while re-generating and they don't want any plastic bits to melt. Once the DPF (and DOC) get hot enough and fuel is added the collected soot ignites and that combustion cannot be stopped just because you turned off the engine.
Don
I think you mean you've had two regens of which you're aware. That's different than having had only two.Quick Storm said:i have had 2 regens in my car since i've owned it. it has 3900 miles on it. [....] i drive it pretty conservative, never really go above 2500rpm, maybe thats why it regens more often than most? what do you guys think?
exactly dawg!, i went back into my training manual for the new bmw diesels, and found that the dpf regens are about every 3-500 miles the systems should be relatively the same. i forgot more than i learned for that training, oh well, thats why they have books.DoctorDawg said:I think you mean you've had two regens of which you're aware. That's different than having had only two.
Considering that regens happen every 300 miles, it is probably not the case that you're having more than most.
http://forums.tdiclub.com/showpost.p...1&postcount=42BCNVC said:I did not read all the post but on one of the most resent posts is 300 miles really how often the regen and how do you know it has or is in the regen mode?
I have all most 4k and have not noticed any regen going on.
Well i did some more reading it looks like it is 3k - 4k no indicators on the dash. If this is wrong that is fine just wanted to let you know I did go back.
Bill
Hi, great info, I tried to monitor a regen today but the "miles since last regen" block is disabled on my VCDS. I just purchased the cable and I'm running their latest software. I believe it is address 108. All the fields are disabled and do not report a value.DoctorDawg said:VAG COM reports miles since last regen. Monitoring this number enables you to determine the ODO at which each regen occurs. For me, its about every 300 miles. I am guilty of having offered misinfo in post #1 in this thread when I said 2000 miles. I did go back and add a bold red disclaimer, but maybe I should go back and just delete my original post, or somethin. I've hesitated because I'm not sure whether a thread survives the deletion of its OP.
I had taken the car in for a MIL light a few weeks ago and the dealer ran it for 80 miles to complete a regen, I got the car back with 90 miles or so on the trip odo.cbauer4 said:I think I have nailed down a possible "regen" indicator. Block 105,2 is currently called requested regens. I think it is really a DPF state indicator where:
0=Clean
1=Very Low Load
2=Low Load
3=Part Load
4=High Load
5=Very High Load(Regen Time)
I know the wording could be better but you get the idea. Everytime my car gets to level 5 the vehicle goes into regen within a couple seconds(confirmed by some other blocks). Can anyone confirm or dispute this? Its not an absolute regen predictor but my car always goes from level 4 to 5 in less than 50 miles(highway travel). I would like to hear from somebody if their car doesnt follow that schedule.
Question #1 - It is not necessary to leave the car running. The only purpose for the fans running is to prevent the heat generated during a regen from melting any plastic bits under the hood. If the regen has not completed, it will just start again as soon as the exhaust temps get high enough the next time you drive. Not a big deal.sowegatdi said:1) Should I leave the car running until the fan stops running?
2) Would the "coasting downhill" and subsequent low speeds trigger a
regen?
One minor correction to a very good post:JSWTDI09 said:If the regen has not completed, it will just start again as soon as the exhaust temps get high enough the next time you drive.