[gregsX3dieselusa]

Newbie X3 diesel owner here.
A couple weeks ago I bought from a private party a 2016 X3 diesel (28d x drive) – California vehicle with 65,000 miles on it. The previous owner always serviced it at the local BMW dealer and it had a few minor issues over the past couple years covered by warranty. It passed smog when we did the sale. No CEL or other issues when I got it. Then a few days after I took possession of it the 1000 mile add DEF warning came up. I added a new 2.5 gallon jug of DEF and the warning cleared. Then a few days later we went on a long 500 mile trip to Reno. It ran great and did real well in the snow through Truckee on I-80. But, the next day a 200 mile no start “wrong exhaust fluid” warning came up. I took it to an independent BMW shop in Reno and after the diagnosis found the DEF metering nozzle clogged up. They cleaned/tested it and cleared all the codes, reset “adaptions” , topped off the DEF tank, etc. I drove away with no codes. Then a couple days later on the way home the 200 mile “wrong exhaust fluid” no start warning pops up again! So the entire 500 mile trip home I didn’t shut it off and the warning message said “blank” miles for no start. At home I shut if off and tried restarting it and it started! Turned it off and restarted again. Awesome. Still starts. I now discovered I still have a few miles left on the emissions warranty (70k miles for California) so it’s next engine start attempt (I hope) will be going to the dealer to get it fixed and hopefully they will cover the repairs under warranty. I checked the fault codes with my OBDII reader and it has permanent P20EE and pending P207F. the P20EE is a NOX efficiency problem so sounds like the DEF is still not injecting correctly.

Questions:

1) The technician in Reno who was a very experienced BMW tech said he had never seen any BMW not start when the no start warning hit zero miles. That was the case with me. Have others had this experience as well? Could it be a fake warning to scare owners into getting their emission system issue fixed? It seems to me that BMW wouldn’t want the liability risk of someone getting stuck in the middle of the Nevada or California desert on a hot summer day or cold winter due to an SCR issue that does not affect engine operation. As I said above, when mine hit zero miles (blank miles actually) the car did not go into limp mode. Nothing happened. It drove normally and it did restart when I got it home.

2) From my research it seems the SCR/DEF system in the diesel BMWs are not reliable/a weak link. I was hoping to keep this car well for a few years and well beyond 100,000 miles. I’d love to hear from other diesel owners about their experience with high mileage SCR systems. What else can I expect with high mileage SCR (NOX sensors, DPF, electronics, etc. ).

Other than above the long ride from Reno to home was great. If anyone has gone down I-5 in central California you’ll know the average traffic speed is between 80-90 mph. It’s the “autobahn” of California. That was an easy cruising speed for the X3 diesel and it still got over 30 mpg. But, the fuel cost savings were easily wiped out with these SCR problems.

Thanks! and sorry for the long post.

[pungo]

Welcome to the forum...

Sorry, can't help with your issue, though you might also try asking in a forum that has more members with the same engine since I don't believe there are a ton of people with a 28d in this forum. I know when I was looking used, it was extremely rare to see one.

[raddoc]

Most of the components of the fuel delivery system are likely covered in the federal emissions system warranty for 8 years/100K miles. Try using a BMW dealer so that if they can find the problem you'll have warranty coverage and BMW corporate to lean on.

[andreigbs]

Agree with raddoc: find your nearest BMW dealer and let them fix it under the 8/80 warranty.

Replacing the SCR metering valve isn't too bad, if that's the only issue. If you were in any other state, I'd recommend finding a good tuner and turning off the SCR/DEF system entirely.