2012 Passat TDI ~ urea injection & BioDiesel questions

I've got a 2010 TDI Jetta that the family loves, thinking of adding in a 2012 Passat TDI in the springtime.

Do I understand it correctly that the new Passat uses a urea injection system?

If so, then why can't it run on BioDiesel? I thought the BioDiesel gummed up the emissions system and therefore we are limited to 5% Bio. But if the Passat is using a urea injection system to achieve clean emissions then would it be logical to presume that a higher % of Bio-to-Dino could be used?

Yes, the 2012 passat uses urea for NOx control.

Good question about bio use. Note both the JSW and have Passat particulate filters. The post injection may be maintained on the Passat to burn the DPF clean. The concern about bio is that in the post-combustion injection, not all fuel burns and some condenses on the cylinder walls and then blends with lube oil.

No expert here on emission controls, so the above is about the limit of my knowledge. Good question and I'm sure others will jump in...

Melensdad said:

If so, then why can't it run on BioDiesel? I thought the BioDiesel gummed up the emissions system and therefore we are limited to 5% Bio. But if the Passat is using a urea injection system to achieve clean emissions then would it be logical to presume that a higher % of Bio-to-Dino could be used?

Click to expand...

Yes the Passat uses Urea injection, but this does not effect the need for 5% bio or less. The Urea is because they cannot use the NOx storage catalyst used in the lighter Jettas and Golfs. It must use SCR (Selective Catalytic reduction) to eliminate NOx compounds. However the reason for the <5% bio requirement has to do with oil dilution and the DPF and neither of these has anything to do with NOx, SCR, or Urea. Sorry, but these two parts of the emissions system are totally separate and not related at all. The 5% Bio requirement still stands - it has nothing to do with the Urea injections system. Sorry if this bursts your bubble.

Have Fun!

Don

If you can get rid of the DPF you can run higher bio % with the ECU programed to know there is no DPF.

@740GLE: Interesting. I have a 2012 TDI Passat (American) and was looking into biodiesel after watching the FUEL documentary. Where or who does type of programming on ecus? I'm in Texas, btw.

Try Malone tuning. This is highly illegal in the US, so most US tuners won't touch it. However, Mark Malone is in Canada, so he doesn't have to worry about US laws (however, you might want to).

Have Fun!

Don

JazzBeBop said:

@740GLE: Interesting. I have a 2012 TDI Passat (American) and was looking into biodiesel after watching the FUEL documentary. Where or who does type of programming on ecus? I'm in Texas, btw.

Click to expand...

JazzBeBop,

As a 9 year user of B100 in a 2002 Jetta and two 2005 Passat TDIs (200K miles total), I do not recommend doing any of this on the new 2012. I have resolved myself to the fact that my new 2012 TDI SEL will NOT run on B100 anymore.

You just bought a $30000+ car with the cleanest emissions ever and great fuel economy and you are going to trash the emission system illegally and void the emissions warranty just to use a higher concentration of BD? What do you hope to gain by doing this?

You are a newbie TDI'er and I know you are still exploring this but from a veteran user and TDI owner, I strongly recommend you do a LOT more research on aftermarket tuning and what is really being said here. It is not a simple switch setting somewhere and a simple mechanical change and it costs $$$$.

First you need a new ECM ($300 or more) in order for it to be tuned, unless you want to wait without a car while you ship it off to be reflashed. It then it needs to be reflashed (shipped off and waiting again or a second ECM) or it will be reflashed by the dealership whenever you go in for warranty work. This requires you physically swapping out the ECM in the car.

IMHO reflashing and these modifications are too much work for the newer models and I will get flack from here, but be aware this site is sponsored and run by VENDORS selling products which include the flashing. I am sure I will hear about this, but hopefully the truth is allowed here since I learned this many years ago.

You buy the right car for what you want. In this case for B100, the 2005 Passat TDI's were the last ones able to run on it without modification or issue, I know that purposely and why I have kept them for so long.

Unless you are going to use homebrew, most B100 Biodiesel these days cost MORE than Dino diesel. Are you looking at running homebrew? While I have produced B100 myself from the Appleseed Generator and under Girl Marks guidance, it was not worth all the time and energy. You must be really careful of the quality and bad fuel WILL VOID the warranty if something goes awry.

This is just MY opinion on the whole subject. I understand there are others who want more power, better performance (their perspective), flip the middle finger at the EPA and emissions controls, or with other agendas and they are entitled to them, but be aware of who is suggesting what you should do before potentially damaging a BRAND NEW $30000 car, especially a new model line.

No one has seen this ECM or coding yet or even physically inspected the new engine and exhaust systems and everything is simple on an overview. It is the details that matter.

@TomB: I understand that the 2012 Passat TDI engineering is new and all. I also did more research on what are the ramifications of using B99 or B100 on all the hoses, gaskets on fuel pumps, voiding warranties, being car-less in Texas...It's like not having internet, but worse. I was really surprised that anyone would have something after-market already. It seemed a little too good to be true. The reason for biodiesel, is to get off the grid. TODAY, I heard that in the U.S. military has been given the green light to blow Iran into oblivion. Thanks to a so-called used-car salesman. So the idea of having an alternative to "Bush/Cheney"-dependent fuels seems very appealing.

Hey Noob... keep your politics to yourself. Not tolerated here, nor will you.

MyAvocation said:

Hey Noob... keep your politics to yourself. Not tolerated here, nor will you.

Click to expand...

Funny that has never stopped anyone on here! Guess you only don't want it when its not your opinion.

Besides who made you the decider when it comes to free speech?

Where have you been, Tom? Not tolerating political banter is a long standing rule on Fred's. Has no place here. Hundreds of other sites for that.

JazzBeBop said:

@TomB: I understand that the 2012 Passat TDI engineering is new and all. I also did more research on what are the ramifications of using B99 or B100 on all the hoses, gaskets on fuel pumps, voiding warranties, being car-less in Texas...It's like not having internet, but worse. I was really surprised that anyone would have something after-market already. It seemed a little too good to be true. The reason for biodiesel, is to get off the grid. TODAY, I heard that in the U.S. military has been given the green light to blow Iran into oblivion. Thanks to a so-called used-car salesman. So the idea of having an alternative to "Bush/Cheney"-dependent fuels seems very appealing.

Click to expand...

There are always posts with ignorant statements in them. You however have been able to include more than one in your post.

MyAvocation said:

Where have you been, Tom? Not tolerating political banter is a long standing rule on Fred's. Has no place here. Hundreds of other sites for that.

Click to expand...

As a veteran I also know what REALLY goes on here. Fred has been out of the picture for a LONG time too.

TomB said:

Fred has been out of the picture for a LONG time too.

Click to expand...

Fred is still the administrator plus he owns the servers and pays for the bandwidth (with the help of donations from members and vendors) that keeps this place running. Therefore, Fred is still very much still in the picture and in charge. There are also a number of moderators who volunteer their time to try to keep this place civilized. Any of these moderators (or Fred) can still enforce the forum rules and they can suspend or revoke any members posting privilege at any time. Some conversations do sometimes go a bit political, but when they go too far the thread is unceremoniously locked. Please do not be the person who gets this thread locked. Thanks.

Have Fun!

Don

I am with myavocation....keep your politcal BS for other sites....this is a TDI site

I'd like to inject something in here, if I may.

We saw several 09s run B100 and they didn't have fuel system problems, but the DPF gave it high hell. So, to me, there is no evidence the CR is any less capable of running ATSM B100 than the PD or VE engines before it... the exhaust system, and VWs oil change interval for the sake of "care free maintenance" is the issue.

Drop the oil changes to 7500 miles, and you negate the "reason" for the B5 warning. Of course you're doing this at your own risk.

The urea system will still function, but until someone decides to run the car for a few thousand miles on B100 we won't know what if any effect it'll have. I haven't researched UREA-enabled vehicles on Biodiesel to see.

The commonly available B20 blends have no ill effects on EITHER emissions system, as proven by use and accessibility in the market place over the past 2 going on 3 years now.

So, really, there isn't much reason that the car couldn't run it. In fact I'm suggesting my parents look at the Passat over the SportWagen because of the urea system and its inherent ability to use B50 without regen issues.

This is based on my own readings and assumptions, and we're big boys who aren't afraid to blow up a $25k car. But I will say there's a reason I keep an ALH around... and burn whatever I want in it.

I want to backup my claims here:

The most researched, and really the only known, potential problem with using biodiesel blends in diesel SCR systems involves trace metals left in the biodiesel from processing-sodium or potassium, and calcium or magnesium. "Over time these metals, once they go through the combustion process in the engine, they end up in the exhaust and that ash can attach itself to different aftertreatment devices, including SCR catalysts," Williams says. "And it can attack those devices. After 435,000 miles," the full useful life of aftertreatment systems for heavy duty vehicles, "you'll see a lot of ash from biodiesel-from these metals-and that could foul the catalyst." Williams says on systems where the DOC and DPF are upstream of the SCR catalyst, the chance of fouling will be reduced, but he adds that some metals from the ash, when in a vapor state, can still pass through the DPF to enter the SCR catalyst. He also says some light duty applications have the SCR system upstream of the DPF, in which cases metals entering the SCR is much more of a concern.

Click to expand...

from: http://www.biodieselmagazine.com/articles/3994/year-of-the-scr-system

Correcting myself, if VW used the same DPF that is found on the Jetta and Golf vehicles, there may still be a concern about regen depending upon where it falls in line of the SCR (urea) catalyst. Time will tell, as someone is going to push this experiment.

Also note they mentioned 435,000 miles before there was ash build up that was worrysome, and this is based on industrial engines. That's low, and alarming, for devices designed to go 1,000,000 miles or more... it's not even half the life span, however most VW TDIs don't even make it past 300,000 and they're getting better than the industry average of 8mpg -- so if we did the drawn out math, we can speculate that passenger cars can get by with it because we're toned-down versions of these larger industrial systems.

And, again, if the scope is "we've had a fuel shortage because we're under attack" or insert your fear-based scenario of survival here, you're still better off with an ALH which will run off the motor oil and trans fluid of the gas cars abandoned on the side of the highway... but you could use some stored B100 in a CR and get by.

Ironically if that Urea tank is too low, tho, the computer won't let you start the car. I am friends with a girl at MB and she has seen more of the clean diesel SUVs come in on roll-backs because the customer didn't believe the "10 starts left" warning message the computer gave them.

You can make up your own mind about the gamble. The realistic scope is 20-40% in my lifetime at all pumps, the technology is there for it. The marketing, maybe not.

In the Passat, the DPF comes before the SCR.

The 435k mile life is the minimum filter life for heavy duty diesels. Minimum servicing intervals are 150k. Keep in mind that the DPFs are designed to be removed and cleaned, not buried and hard to remove. Futhermore, some DPF cleaning services will simply swap your clogged filter for a clean core, allowing you to get on the road even faster.

Unfortunately VW decided to combine the oxidation catalyst and the DPF in the same cannister, making it difficult to clean. I don't think anyone stateside has a system for cleaning them. Once people start racking up the miles we'll find a solution for cleaning the ash from the DPFs.

kcfoxie said:

Drop the oil changes to 7500 miles, and you negate the "reason" for the B5 warning. Of course you're doing this at your own risk.

Click to expand...

In my testing on the Jeep with the DPF with CRD and post injection regens I saw oil dilution on as little as 1000 miles of B100. As well the dipstick oil level INCREASED substantially.

So cutting the oil change to 7,500 miles will NOT solve the mechanical wear issues associated with the oil being diluted by the B100 washing past the piston rings.

Anyone thinking of doing this MUST do Used Oil Analysis every 1000 miles and look for fuel contamination, flash point changes, viscosity changes and let the testing company know what you are doing. They will look for other impacts known to occur with fuel getting into the oil.

Are UOA companies looking for just D2 and notFatty Methal Esters of Bio? or can they pick up FME in the oil?

OK the issue I have is owning a 2012 Passat TDI that needs a fuel fillup about once a month and finding today that the locations I usually go to get my fuel are now running "not more than 15% Bio diesel". First of all what does that mean? It could be 15% but it might be 12% or maybe its 5%. Secondly do I now get to go back to the dealer and ask them for a list of stations in the immediate area that are selling 5% or less? I am sure they have that list right and that it will be updated on a monthly basis? Of course if I want to take a trip to get that 700 miles to a tank who do I go to to get the list of the stations I can use along my trip route that are sellin 5% or less. VW is selling a product that basically requires you to start your search for allowable fuel when you have a half a tank left! I picture myself in the middle of Kansas having stopped in several stations only to find out NO ONE is selling anything less than 20%. What am I to do have some flown in from the last station I was able to find. This has class action law suite written all over it! SEVENBLOCKS

hasn't VW said that these engines and warranties are good in those states that have mandated higher percentage of bio? Such as Illinois that is now running B11 at most pumps. I know the Love's by me has switched to B5 as the tank claim but the stickers say may contain up to 15%.

Sevenblocks, I would not worry too much about an occasional fill at up to b20.

VWoA needs to release a document, stating IN WRITING that bio up to 20% is acceptable.
The future is now, and they need to address it immediately.

Actually I would say that the future is yesterday and VW needs to catch up.

The service director at Marten's VW (Bethesda Md) has promised to get an email out today to his superior. He is as interested as I am (so he says!) how VWoA is dealing with this in the midwest (it's not an issue here, as we just don't have bio...yet)

All you folks in states with mandatory bio >5%: Have you asked your VW representatives about this?

My salesmen is going up the chain as well from here in San Antonio. Just to really muddy the water.....while the sticker on the pump says up to 15% bio it also says good for use in ANY diesel car. That very visable rule reminder is more powerful than the hidden note in your owners manuel that we look at now and then. KJCLOW I agree I should not worry about an occasional fill but this is going to be a constant no option thing for me and over time perhaps for all of us. VW is selling a car that requires what is becoming special diesel fuel. Diesel is not at all stations as it is and now just because a station has diesel doesn't mean you can use it....the situation is crazy and VW needs to address it quickly as tdiatlast has indicated.