How do I kill my DPF as fast as possible?

coolusername

Well-known member
Joined
May 4, 2022
Location
Orange, CA
TDI
2012 Jetta Sportwagen TDI
So I've got a 2012 Jetta Sportwagen TDI. Love the car, it's in great shape, currently at 76k miles. I'm getting extremely poor fuel mileage, like 25 MPG on the highway while driving like a granny. DPF regenerates super frequently too, like every 150 - 180 miles. Took it to the dealer, but they won't replace it without codes. I have until May when my Dieselgate warranty runs out. In the meantime, if my DPF were to get clogged up, I'd get a new one, and that would most likely fix my fuel mileage problem (I've already checked the bajillion other possibilities in the Fuel Economy thread, except for the EGR. Car's too new for that to be an issue anyways). Do you guys have tips for things to do to stress the DPF and create additional soot? Accelerate clogging it up? Already I have a very short 5 mile commute, that stresses the engine out because it's up a hill. Lots of cold starts too, and I'll be driving the piss out of it in "S" mode for all of this. I have a PolarFIS so I can see when the car's trying to regen, and I can then purposefully interrupt it. I understand that 24 grams of calculated soot is when the car starts to want to regen, and I need to get up to 45 grams calculated (point of no return) to make certain I'll get a new DPF and that they won't just do an emergency regen or something. So, I need tips. How can I clog up my DPF as fast as possible beyond all repair, but do it in a nice and plausibly deniable, natural way?
 

coolusername

Well-known member
Joined
May 4, 2022
Location
Orange, CA
TDI
2012 Jetta Sportwagen TDI
Your problem is a bad thermostat.
My car gets up to temp though? Hits 180° F according to the PolarFIS. Is the thermostat operating at 10° below normal really what's causing this? This car has really been confusing me for the past few months. Every time I've posted about it I've gotten different suggestions and diagnosises. I've been told my issue has been anything from the thermostat, the DPF, the EGR, my fuel metering valve, or that there's no issue at all.
 

coolusername

Well-known member
Joined
May 4, 2022
Location
Orange, CA
TDI
2012 Jetta Sportwagen TDI
I love the comment "car is too new for that to be an issue anyways".... it is an 11 year old CR TDI, it is already a rolling "issue", LOL....

You should probably just part ways with that car now.
Well, after reading these forums a bunch, I was under the impression that EGR clogging was only really an issue for higher mileage VE TDIs, and that the newer common rails had less problems with the EGR thanks to a redesigned system and the introduction of ULSD over here in the US. My car's also lower miles.
 

oilhammer

Certified Volkswagen Nut & Vendor
Joined
Dec 11, 2001
Location
outside St Louis, MO
TDI
There are just too many to list....
Oh, the old issues are not really present any more, but those were much, much less of a hassle than the new issues. R&R and cleaning an ALH's intake manifold every ~80k miles is nothing compared to the problems the newer cars have.

Borderline thermostats have been known to keep DPF regens from working properly... mileage is not always the only thing, age, and the general weakness of the design coupled with the Dieselgate "Fix" making things worse than they already were are also factors.
 

CleverUserName

Veteran Member
Joined
Oct 25, 2014
Location
NorCal
TDI
2014 OZ Cruze CTD & 2010 JSW 6MT & 2017 GMC Canyon CCLB ATX 2.8 Duramax
My car gets up to temp though? Hits 180° F according to the PolarFIS. Is the thermostat operating at 10° below normal really what's causing this? This car has really been confusing me for the past few months. Every time I've posted about it I've gotten different suggestions and diagnosises. I've been told my issue has been anything from the thermostat, the DPF, the EGR, my fuel metering valve, or that there's no issue at all.
Yep that’s your problem. Start there and do the whole timing belt service. The car got a new DPF when it got the emissions modification by the dealer.
 

coolusername

Well-known member
Joined
May 4, 2022
Location
Orange, CA
TDI
2012 Jetta Sportwagen TDI
Yep that’s your problem. Start there and do the whole timing belt service. The car got a new DPF when it got the emissions modification by the dealer.
I already had the timing belt done when I bought the car. If I had known this was also something to replace I would have done so at the time. Guess it's time to shell out some cash, thanks. Strangely enough nobody mentioned this when I posted in the Fuel Economy thread.
 

Thunder Chicken

Veteran Member
Joined
Jul 19, 2012
Location
Sioux Lookout, Ontario
TDI
2012 Golf Wagon
Driving it like a granny, keepIt as low of rpm as you can stand… lug it….. use the wrong engine oil…. Ie. an older API rated oil…..lots of cold starts, short runs, no highway driving….. Or……
Screw the warranty, you know what you gotta do to let it be happy. You won’t need the warranty if the parts aren’t there! 😉
 

2004LB7

Veteran Member
Joined
Jun 2, 2013
Location
California
TDI
2006 Jetta
Run the car on high sulfur diesel for a few thousand miles. Add a gallon of synthetic motor oil to the fuel tank every fill up. Run the car on W85/black diesel. Idle the car for a few months straight. Put a plastic bag over the air filter. Get it tuned for rolling coal

Any of these may cause an early death to the DPF
 

CleverUserName

Veteran Member
Joined
Oct 25, 2014
Location
NorCal
TDI
2014 OZ Cruze CTD & 2010 JSW 6MT & 2017 GMC Canyon CCLB ATX 2.8 Duramax
I already had the timing belt done when I bought the car. If I had known this was also something to replace I would have done so at the time. Guess it's time to shell out some cash, thanks. Strangely enough nobody mentioned this when I posted in the Fuel Economy thread.
Whiskey Tango Foxtrot? You didn’t know the thermostat needed to be replaced ? Even though you knew it wasn’t getting up to operating temp of 190F? I find that very hard to believe.
 

coolusername

Well-known member
Joined
May 4, 2022
Location
Orange, CA
TDI
2012 Jetta Sportwagen TDI
Whiskey Tango Foxtrot? You didn’t know the thermostat needed to be replaced ? Even though you knew it wasn’t getting up to operating temp of 190F? I find that very hard to believe.
When I first bought this car, I didn't know very much about TDIs. I got the timing belt changed almost immediately because I heard it was an age based thing, too. At the time, nothing seemed off. I had no reason to believe it wasn't getting up to operating temp, because the gauge read straight up and down at 190. I only noticed that the car technically wasn't getting up to operating temp when I got a PolarFIS a few months down the line, and noticed that it said my car was settling at 180 degrees. You know just as well as anybody that the temperature gauge on these cars is vague and more of an "idiot light", and reads 190 at anywhere from 160 to 200 degrees. This entire time my gauge has said I'm reaching "190."
 

CleverUserName

Veteran Member
Joined
Oct 25, 2014
Location
NorCal
TDI
2014 OZ Cruze CTD & 2010 JSW 6MT & 2017 GMC Canyon CCLB ATX 2.8 Duramax
When I first bought this car, I didn't know very much about TDIs. I got the timing belt changed almost immediately because I heard it was an age based thing, too. At the time, nothing seemed off. I had no reason to believe it wasn't getting up to operating temp, because the gauge read straight up and down at 190. I only noticed that the car technically wasn't getting up to operating temp when I got a PolarFIS a few months down the line, and noticed that it said my car was settling at 180 degrees. You know just as well as anybody that the temperature gauge on these cars is vague and more of an "idiot light", and reads 190 at anywhere from 160 to 200 degrees. This entire time my gauge has said I'm reaching "190."
It’s not just the timing belt that gets changed, it’s supposed to be the: thermostat, water pump, idlers, and tensioner. Some people also do the camshaft seals. If you just had them replace the belt then it all needs to be redone.
 
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