[Ryballz]

Last time it was added was something like 17k miles ago, since then it's never popped up the warning to add more.
The car was involved in a minor rear end accident that caused the rear bumper and trunk to be replaced, I wonder if the body shop somehow disconnected the DEF crap.

No CEL or anything to note, car seems pretty normal.

[GreekboyD]

I highly doubt it. You're most likely running low on it.

[yatzee]

how long should we be able to go between fills?

[F32Fleet]

Originally Posted by yatzee

how long should we be able to go between fills?

Approximately 1 oil change interval but it correlates to fuel usage.


17k miles sounds excessive and the OP should get a SES. Maybe the OP is off with his mileage.

[Got_Diesel]

Originally Posted by Socom

Approximately 1 oil change interval but it correlates to fuel usage.


17k miles sounds excessive and the OP should get a SES. Maybe the OP is off with his mileage.

if you get high gas mileage, you'll use less DEF than if you get poor mileage. I think for every gallon of diesel, 3% of a gallon of def is used.

[Ryballz]

Originally Posted by Socom

Approximately 1 oil change interval but it correlates to fuel usage.


17k miles sounds excessive and the OP should get a SES. Maybe the OP is off with his mileage.

If anything it's longer than that.
The last time the car was serviced by BMW was before the warranty ran out, just under 48k. My independent doesn't stock DEF, so I figured I'd just add it myself when the warning pops up.
Car is nearing 66k now.

[Ryballz]

Originally Posted by Got_Diesel

if you get high gas mileage, you'll use less DEF than if you get poor mileage. I think for every gallon of diesel, 3% of a gallon of def is used.

According to that, if I divide my mileage by my average mpg, I should have used nearly 17 gal of DEF in that time. I think the tank is like 6.

[kbsilver]

Think it's closer to a 1% ratio, but no more than 1.5%. At 1 % you should be turning on the 1000 miles to no start any day now. Think it's impossible to stop using DEF because there are too many sensors monitoring the exhaust stream. For example if you filled the DEF tank with water and the conversion to reduce NOx was no longer occurring it would know and you will get a SES.

[Ryballz]

So since I've made the thread I've gone another 2200 miles. Now showing 19,300 since the last fill at the dealer.
No SES, or warning.

But, the car is doing a DPF regen just about every other time I drive it it seems like. Mileage has fallen off also as a result.

[F32Fleet]

Originally Posted by Ryballz

So since I've made the thread I've gone another 2200 miles. Now showing 19,300 since the last fill at the dealer.
No SES, or warning.

But, the car is doing a DPF regen just about every other time I drive it it seems like. Mileage has fallen off also as a result.

DPF regeneration is not related to DEF usage.

It has been a couple of weeks. Why haven't you had the SCR system checked?

Are you SURE about the mileage?

[Ryballz]

Originally Posted by Socom

DPF regeneration is not related to DEF usage.

It has been a couple of weeks. Why haven't you had the SCR system checked?

Are you SURE about the mileage?

Positive about the mileage, I confirmed by finding my last service receipt from BMW which was over 19K miles ago.
My independent shop who does maintenance since the warranty has expired doesn't stock DEF. I've been waiting for the light to go on, and I'll add it myself.

I usually get good mileage with my car, my lifetime average is around 37mpg. But even so I'd always need DEF at every oil change, and once I needed it 2,000 miles before.

I haven't had it checked because obviously the car is out of warranty.

[F32Fleet]

Originally Posted by Ryballz

Positive about the mileage, I confirmed by finding my last service receipt from BMW which was over 19K miles ago.
My independent shop who does maintenance since the warranty has expired doesn't stock DEF. I've been waiting for the light to go on, and I'll add it myself.

I usually get good mileage with my car, my lifetime average is around 37mpg. But even so I'd always need DEF at every oil change, and once I needed it 2,000 miles before.

I haven't had it checked because obviously the car is out of warranty.

Very strange indeed. Keep us posted.

[Ryballz]

Warning came on the other day finally.
Mileage was at 20,200 on the previous fill of DEF.

I could live with that