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Old 08-30-2012, 06:45 PM
boooomer boooomer is offline
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Location: Boynton Beach Fl.
Join Date: Apr 2010
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Mein Auto: 'BMW 335d, Audi A3
Originally Posted by firstbimmer View Post
Anyone experienced an increase in DEF usage after the EGR recall/reprogramming?

I am at 32K. My DEF warning never came on between oil changes at 13K and 26K. Both oil changes indicated on the sheet that they refilled the DEF.

That means I went 13K twice with no DEF warning. I just had my DEF warning come on 6K after my most recent oil change?!? That seems like a huge change in usage while my driving habits haven't changed.

I asked my SA to check the Passive tank because a warning this early could mean that the pump was clogged between the passive and active. He said there was nothing to indicate a need to check and that it was completely normal for the DEF to run out after 6K. I asked why I had lasted 13K the two previous times and he basically kept returning to the 'its totally normal" and "I have people come in all the time after that few miles."

I just find it highly unusual that my car would go 13K twice with no warning, and then only go 6K this time. From my perspective, either they lied on my sheet at the last oil change and didn't refill the DEF, or the pump isn't working between the active and passive tanks and the warning came on after the active tank was getting empty and the passive tank wasn't getting pumped over to refill. Is there anything I can do to have them check this pump while still under warranty? I don't want them to push me off for the next 16K miles and then have it fall on me out of warranty.

Ideas? Thanks!
Your SA is BSing you. 6k is NOT normal. Or it might be normal for THEIR dealership because they might not be filling the tanks properly. You are correct to be concerned about it. The manual says that the DEF should not need refilling between services...unless there are certain conditions - like driving in extreme altitudes.

And It's been well documented here that it's usually a problem with under-filling on the previous service or a mechanical problem. I would try to get to the manager.

I don't know if a clogged or failing transfer pump throws a code. But as a courtesy they should check it for you.

Did they top off the tanks for you?

One clue is how much fluid it took to top off BOTH tanks. If the pump is functioning then both tanks should have been empty and it should take 5 - 6 gallons. In that scenario the dealer probably under-filled the tank on the previous service. If it only took a fraction of that amount then I think there is a greater chance of a transfer pump malfunction. Of course that's all on the assumption that they know what they're doing and checking both tanks!

One other question - did your previous service paperwork show the number of DEF units added to the the tanks (Each unit is 2.5 gallons)? On my last two 13k services, the car took 2 units which indicates a "normal" use rate - in spite of the fact that a lot of my driving has been in Santa Fe NM, 7200' above sea level.

Good Luck!
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