Filed under: Maintenance, Hybrids/Alternative, Government/Legal, Green, Mercedes-Benz
New diesels won't run when the urea tanks is dry
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Click above for a high-res gallery of the MB GL320 BlueTEC
Owners of the new crop of clean diesels will have another maintenance item to concern themselves with if their new cars are equipped with urea injection. The EPA requires that all diesels meet strict new emissions standards, which almost always requires the use of either a NOx trap or urea injection. To ensure that the system is working, a sensor checks both the level and the quality of the urea solution and will keep the car from starting if the tank is empty. The new VW Jetta TDI doesn't use urea, but the new Mercedes-Benz BlueTEC vehicles do. According to Mercedes, a counter will appear on the dash when there are twenty starts remaining. If the driver ignores the message, the car will not operate until at least two gallons of urea solution is added to the tamper-proof tank that resides in the spare tire well.
Engineers have designed the urea tanks to be large enough to last about 15,000 miles. This should be large enough that drivers never run out, as the tanks will be checked at every schedules service. As an alternative, small bottles of the urea solution will be available for owners who want to maintain the system themselves. The cost of the urea solution, which MB refers to as AdBlue, will mirror the cost of diesel fuel, so a refill shouldn't cost more than $30 or so. Before anybody asks, yes - urea is a component of urine, and no - peeing in the tank will not fool the sensors. You've been warned.
Gallery: 2009 Mercedes-Benz BlueTec SUVs
[Source: Automotive News - sub. req'd]
Reader Comments (Page 1 of 3)
Gabagool 4:39PM (10/20/2008)
Just pull to the side of the road and peee into it.
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Yar 5:17PM (10/20/2008)
I don't know about you, but I can't piss out 2 gallons on a whim.
Kotse 5:27PM (10/20/2008)
...mine comes in a sparkling Martinelli bottle. ;)
Snark 5:56PM (10/20/2008)
You people are aware, right, that urea is not urine? That urea isn't even obtained from urine, that it's synthesized in a lab? That urea solution doesn't smell, look, or work like piss? That you're making your lack of education as abysmally obvious as your stunted maturity?
Just checking. Because to those of us who survived to about age 25, and paid attention in school, you sound like a moron.
ChopperDave 6:20PM (10/20/2008)
Or maybe, and I'm going to blow your mind, here, Snark, some of us are kidding and like the simple pleasure of a joke about bodily functions. That, and--again, blowing your mind--you have no sense of humor.
Gabagool 7:04PM (10/20/2008)
@ Yar, well i don't like to brag but you know......you know....two gallons is not a problem for me seeing as my unit is ..............
tekd 8:27PM (10/20/2008)
@Snark
Urea isn't urine but in theory you could attempt to make your own AdBlue solution in a pinch if you had a lot of pee. A human being's daily pee can have up to approximately 35 grams of solid urea in it (although usually it's less than this). So if you've held in your pee for the whole day on a long road trip you might have enough urea to make almost 100cc's of this solution or a 1/10th of a bottle. It's just made up of distilled water and urea (approximately 2 parts water and one part urea by weight). Really, if you have an entire car full of people who haven't peed all day, and you ran out of urea in the middle of nowhere (I doubt AdBlue is going to be easy to get when there aren't dealers nearby), you could probably make your own pee version of it. You'd just need to get something to boil pee in and a few bottles of isopropyl alcohol and distilled water, then boil off your pee until it's thick and syrupy, add the alcohol, boil it down again (making sure not to set yourself or your car mates on fire while doing this since it's super flammable, so have a chemical fire extinguisher ready), add distilled water water, boil it down again-you might have to repeat this a few times to separate out the urea, but finally you should be able to crystallize off somewhat pure urea (this is not the most efficient way to get urea at all but probably the only way you can do it with stuff you can buy anywhere). It'll look like a bunch of crystals sitting in an oily yellow goop at this point, and you can grab a coffee filter and pour this goop onto it. The other stuff should filter through leave the urea crystals on the top. You can probably repurify these crystals by again dissolving only these crystals in distilled water or alcohol and boiling it down and letting it crystallize then refiltering. Then just dissolve the crystals in distilled water equivalent to 2x the weight, and voila-ghetto AdBlue solution.
Of course, since this all takes an obscene amount of time you'd probably end up holed up in some motel boiling your pee in alcohol when the cops kick down the door thinking you're a meth dealer, lol.
Yar 8:56PM (10/20/2008)
@ Gag
Your "unit" has nothing to do with storage capacity, so unless you have a bladder the size of a beach ball I'm still calling BS.
Swede 4:40PM (10/20/2008)
I'd pee in it even if MB said I shouldnt.
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Swede 4:40PM (10/20/2008)
All comments should now be about pee.
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MachinaDC5 4:54PM (10/20/2008)
Agreed. That is, urine the correct mindset on this one.
Travis 4:41PM (10/20/2008)
There's a bunch of other hacks / fake sensors that allow people to get around everything from removing the Cat to installing a turbo or CAI. Doubt it'll be long before people can find a way around this as well...
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FThorn 4:46PM (10/20/2008)
Uh, that would be illegal!!! I can't believe you're honestly suggesting breaking the law. We live...in a SOCIETY!
I drive the speed limit everyday! Don't you????
Gabagool 4:53PM (10/20/2008)
The law violates his civil right to pollute.
I for one am tired of the clean air and clean water.
havoc 6:12PM (10/20/2008)
yeah, i'd have to imagine that just like other sensors, it's just a voltage lead from a float in the tank. you could prob just tap another voltage source or etc to 'trick' the system. i can see an 'emergency bypass' to allow you to get to the urea filling station, which of course will be on diesel pump #3.
yup it's illegal and for off-road use only.
BigMcLargeHuge 4:51PM (10/20/2008)
Wouldn't it be nice if you could fill up the fuel tank and radiator with pee as well?
Pee-cooled, pee powered with pee injection.
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why not the LS2LS7? 4:52PM (10/20/2008)
I'd pee in it anyway. Especially if it left me by the side of the road like that.
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Jeeza 4:54PM (10/20/2008)
chances are the urea tank only has a level sensor that feeds the ECU with info. So if your stuck just fill it with water! the ECU will just read a level and it will indicate that it is full.
But you wont be emmisisons compliant!
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nataku83 4:56PM (10/20/2008)
eh, they'll probably use something a little more complicated, maybe measure the resistance of the solution or some other electrical property.
ChopperDave 4:55PM (10/20/2008)
I'll sell you my own special blend of urea for half the price!
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