2016 X5 F15 xDrive40e - fueling problems

[kstinmb]

Ok, on a trip 500 miles from home our 2016 X5 40e hybrid won't take any gasoline, it just chokes and the backflow immediately shuts off the pump nozzle. Pressing the gas cap door release button (lower left under dash) did not release the door lock, so I had to pop the cover over the fuse bank in the right rear and pull the emergency door release. And we have a check engine light.

So with enough gas still in the car, it's 90 minutes to the Knoxville TN dealer. They swap the fuel pressure sensor, which was replaced, also under warranty, back in 2019 when I bought the beast fresh off a 3-year lease with only 11,000 miles. This X5 has stop/start, so I understand the tank is pressurized.

Two days later I pick up the car and right away it chokes again trying to fill the tank. Wtaf? Back to the dealer, whose tech is stumped. :-( They will keep the car over New Years to try again next week, this time to replace the "tank isolation valve and hybrid pressure refueling control unit" for $1.5k. Meanwhile we drove home in a rental to wait for the fix, which is $50/day. Also :-(

Has anybody else been here? Is the tech looking at the right parts? This is an out-of-the-blue issue for a car that has otherwise been happy for 5 years. We are low-mileage drivers (retired), only drive this car about 6k miles per year, with lots of battery-only local errands.

Thanks for any info and Happy New Year!
2016 X5 xDrive40e (and 2014 i3 BEV)
Myrtle Beach SC

[RED_Y_]

Seems like there is a procedure to calibrate the sensor, check this thread out:
https://f15.bimmerpost.com/forums/sh....php?t=1561089

[kstinmb]

Originally Posted by RED_Y_

Seems like there is a procedure to calibrate the sensor, check this thread out:
https://f15.bimmerpost.com/forums/sh....php?t=1561089

Thanks. We're on the third fuel pressure sensor, but the problem seems to be deeper. They'll have the parts on Wednesday the 3rd and then let me know.

Apparently they only swapped the pressure sensor last week according to the codes and instructions, but didn't actually try to refuel. They would have seen that it still wouldn't take the gas and maybe had it properly repaired on Friday. Now I have a week or more car rental and another 1000 mile round trip to pick it up.

Happy New Year!

[kstinmb]

Here's a follow-up - in the week after New Years they swapped out 16137303949 (Evaporative Emissions System Leak Detection Pump) and 16145A08530 (Pressurized Fuel Tank Control) for about $1450, a third of that was labor. The service advisor then fuel-up on his own dime to verify that the car would actually allow refueling. Then, instead of driving to Knoxville to pick, it up, I had it shipped back to Myrtle Beach SC, which was about break-even deal for me out-of-pocket (compared to a rental car, gas for 2000 miles and an overnight in Knoxville) and I didn't have to drive through the snow storms the second week of January.
We are low-mileage drivers so it will take a while until it needs gasoline again and I can test the refueling.

Overall I would fault the dealer for only seeing the fuel pressure sensor fail code and replacing that without checking whether it would take gas. The second time on their rack the tech saw codes for the additional parts - why didn't he see them the first time? My additional expense was the rental car for a week and shipping the car home, so not a big deal, but not how I would have liked.

I had them keep the swapped parts for me, but they will not be evaluated to see why they failed. Each year there is less and less interest in what's breaking on the F15s. This may be the last car I ever buy - we paid it off early - and with my OCD attention it may last.

[suitedcboy]

Plug-in hybrids have a unique fuel tank system. The tank has to be sealed and tolerate pressure as the miles you drive on battery alone sloshes the fuel and makes vapor but the gasoline engine is not running to allow the normal venting through engine where the fuel vapor can be burned instead of some of the liquid fuel. There is a safeguard for excessive pressure where electric drive continues but engine is started just to have the fuel vapor disposal via engine consumption of that vapor. Since the tank can have pressure and you might choose to fuel it while there is pressure, the system will not let you have fuel cap access until the tank is vented through fuel vapor storage charcoal canister. The fuel cap release button tell engine control system to vent tank but fuel door lock is not unlocked until the pressure is released. Hopefully the components they replaced have addressed why it was not venting on command and releasing door lock. The fueling problem would be the result of the vent valve that is integral with that leakage detection pump not opening or commanded open and the fuel vapors were not escaping which lets fuel burp back out through filler cap opening. The auto shutoff on fill nozzle from fuel station pump has the full sensing and fuel vapor escape or fuel escape shuts off nozzle.