FYI: DPF regen info from my '09 TDI - Page 7

HumbleSmoker · February 9th, 2009, 17:56

Raised idle after cold start because its heating up the DOC/DPF Monolith as quickly as possible to keep emissions down.

bigman111387 · February 10th, 2009, 16:01

O ok ic. Makes sense

newbury · February 10th, 2009, 16:24

I would probably go buy a VagCom and a small laptop just to monitor my JSW if I could be sure to find out in advance when a regen was probable.
Based on earlier posts in this thread it looks like 320 to 400 miles is a limit. My quandry is determining the last regen.
I've a range of vehicles to drive and if for example I knew a regen was due I'd hold off driving the JSW for short trips.

Jack Frost · February 21st, 2009, 05:32

Quote:

Originally Posted by DoctorDawg

Beetle98, I would guess that the fan was involved in a regen. I know that when I've shut down during a regen, after starting and stopping the engine again the fan would go off (just like you report).

I haven't mentioned this before, but my nose can detect a very slight, but quite distinct smell associated with regens. Smells like the tiniest whiff of bleach - not strong, just subtle. Maybe its just 'hot metal' smell, I don't know, but its distinctive.

I may have had my first experience witnessing a regen. I just pulled off the highway so my wife could pick up the mail. While she was gone, I opened up the driver's door and could hear the engine idling with some vigour. I looked at the tach it was idling at 950. I could detect a faint whiff of a hot dieselly smell.

Unlike everyone else, the radiator fans were not going. Perhaps this was because the air temperture was -20 C and the cabin heater fan was going.

When I got home, before shutting off the engine, I notieced that the idle had returned to 850.

jtml · March 5th, 2009, 23:31

Mine did it last week one night, at the post office parking lot, after driving 5 miles. All I noted was that it smelled hot, and the fan came on for about 5 minutes while parking.

nesdon · March 15th, 2009, 10:06

My anectotal experience with running both petro and various alkyd ester fuels (homebrews and commercial B99) in both cars and generators has been a decrease in soot with biodiesel over petro.

Seems like monitoring regen could get hard data on this, and that B99 could make up for some of its energy density deficit by reduced regen cycles. I'm really jonesing for one of these cars, if I get one I'll do some studies.

I accept the expence and effort of biodiesel for the satisfaction of knowing that none of my driving is funding the purchase of suicide vests. It really is a fact that the 20 plane tickets used on 911 were bought with oil profits.

DoctorDawg · March 16th, 2009, 15:41

Quote:

Originally Posted by nesdon

Seems like monitoring regen could get hard data on this, and that B99 could make up for some of its energy density deficit by reduced regen cycles.

On my '09, at least, regens happen every 300 mi. like clockwork. I suspect this is the ECU's default behavior, so I'm not sure that monitoring regens will tell you anything.

nesdon · March 16th, 2009, 17:16

Quote:

And I absolutely agree with you, Otto; at one regen per 2K miles,

I guess I misunderstood this comment. It sounds like regens are calculated by the ECU, I presumed based on pressure differential across the filter.

DoctorDawg · March 18th, 2009, 16:52

Yes, in my original post in this thread I mistakenly reported a 2K mi. interval between regens, due to misleading info reported by the ECU (or, at least, confusing info). But I went back and retracted that; elsewhere in this thread you'll see that I now get regens every 300 mi. 2K woulda been sweet. Sorry for the confusion.

nesdon · March 19th, 2009, 23:23

Well, I broke down and bought one. So I will start collecting data on my own. It is a pretty sweet ride, one day into it, the six speed manual is surprisingly confusing. I stalled it more than once today.

But 65 mph at 2K RPM, now that's making use of all that torque, way more than my AHU. Plus my number one son is ecstatic with that hand me down.

He grumbled and whined when I forced him to drive a '85 Golf as his first car. But he became the hero of his homies when the sexy 60's muscle cars his friends' rich dads had bought them, were coughing and spitting with their cheesy Rochester carbs, pitted points and allowance-busting mileage.

That little car carried hundreds of rave-crazy kids back and forth between Topanga and the Orange Show for 3 or 4 dizzy summers. Paid $1000 bucks for it and he put 60K miles on it with nothing but a battery, a set of brakes and some filters and fuel hose.

Jeffmx5 · March 25th, 2009, 14:15

My wife and I are enjoying her new Jetta. We have had the fans come on when we shut the car down at least 4 or 5 times. One time I had a couple of minutes so I popped the hood and verified both fans were running but the radiator was cool to the touch.

Our concern is will the fans eventually shut off before sucking the life out of the battery?

The only way we have been able to get the fans to stop is to restart the motor and shut it down again. The fans stop as soon as the motor starts. If the fans are running to cool the coolant then they should keep running after cycling the motor on and off because the coolant is not sufficiently cool.

We took the car into the dealer but of course they could not find anything wrong. They did mention that the fans could run on for 10 minutes. We think we have left them running for longer.

Next time it happens I will time it to see how long the fans run for.

Has anyone had the fans come on when the shut the motor off and then had the fans shut off by themselves?

Pelican18TQA4 · March 25th, 2009, 17:46

The fans were probably on before you shut off the engine but they're less noticeable when the engine is running. I have only had it happen twice that I shut the car off during or just after a regen cycle and yes, the fans remained on; only for a couple minutes the second time but the first time they were on for about 8 minutes (yes, I timed it).

AFAIK, the purpose of the fans continuing to run isn't to 'cool the coolant', but to prevent heat build-up in the engine compartment. The regen cycles make the DPF VERY hot and during a regen cycle the fans will come on when the car drops below a certain speed to prevent the engine compartment from getting too hot. If you pay close attention, you'll hear that they shut off once you are underway again and then as you slow they will come back on.

Dieselfitter · April 19th, 2009, 20:33

Pulled into a parking lot today and engine was idling at 1000rpm (800 is normal). Went around to the back and took a whiff of the Exhaust. Slight bleach smell.

Both rad fans were running,but would stop when engine was shut off. Looked under the hood,and MAN, it was HOT between the engine and firewall!!

cbauer4 · April 21st, 2009, 18:46

Quote:

Originally Posted by newbury

I would probably go buy a VagCom and a small laptop just to monitor my JSW if I could be sure to find out in advance when a regen was probable.
Based on earlier posts in this thread it looks like 320 to 400 miles is a limit. My quandry is determining the last regen.
I've a range of vehicles to drive and if for example I knew a regen was due I'd hold off driving the JSW for short trips.

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.

bill09tdi · May 9th, 2009, 17:10

Quote:

Originally Posted by Jeffmx5

My wife and I are enjoying her new Jetta. We have had the fans come on when we shut the car down at least 4 or 5 times.
Has anyone had the fans come on when the shut the motor off and then had the fans shut off by themselves?

As mentionted before in this thread, TSB issued that says it is normal.

I have 20k miles on my 2009 TDI JSW and I've heard the fans running towards the end of a long drive (sitting at a light), then the fans continued running for 2-10 minutes after turning off. I've noticed if you cycle the key back on/off sometimes it turns off right away, but usually I just walk away now. I know it will turn off on it's own and trust that it will.

I've heard the fans running (about 5 times) at temps between -10F and 80F, and there isn't any pattern other than I've noticed it more after driving medium speeds (30mph-60mph) than when driving faster speeds (60mph ++). As mentioned elsewhere it is probably doing it at the higher speeds and cool before I slow down again.

When you have a manual transmission, it is easier to tell when it is doing it because it feels like turbo lag even when it shouldn't. I seem to have to let the clutch out a little slower or I'll stall it. Same as others, RPM will rise to 1000rpm even on a fully warm enging.

I still think it would have been a good idea to put a "DPF in progress light" somewhere on the instrument panel.