BMW X5 Diesel Water Separator?

[windforce]

Long story short, I filled up my 2010 BMW X5 Diesel at gas station and went through the car wash forgetting closing my fuel cap. The car runs fine after the wash.

I am really worried. Is there a diesel water separator built in our SUVs? Please instruct me what my next step should be.

Thank you.

[youry]

I doubt much water was sprayed inside the tank as I assume you topped it of to begin with. The worst case scenario, you probably have one pint of water which is mixed with 20 gallons of fuel. That's something like 2% water 98% fuel. I would fill it up every day for a few days to cut down the overal percentage of water in the tank.

[Doug Huffman]

Originally Posted by youry

[ ... ] I would fill it up every day for a few days to cut down the overal percentage of water in the tank.

?? It is not a serial dilution problem. Diesel and water are immiscible. Once water is in the diesel fuel tank I don't believe that there is anyway to preferentially remove the water.

OPie, consult your favorite service adviser on the use of a drying agent. I used PS White in my VW TDI without issue for more than a decade. I have a couple of gallons of PS Red Diesel 911 primarily for my tractor.

[youry]

Originally Posted by Doug Huffman

?? It is not a serial dilution problem. Diesel and water are immiscible. Once water is in the diesel fuel tank I don't believe that there is anyway to preferentially remove the water.

OPie, consult your favorite service adviser on the use of a drying agent. I used PS White in my VW TDI without issue for more than a decade. I have a couple of gallons of PS Red Diesel 911 primarily for my tractor.

What I meant to say is to add a couple gallons every day (or whatever he uses on his daily routine) to cut down the percentage of water from 2% to almost no water.
I remember back in the days, in the eastern part of Europe, gas owners would add 10-15% water in the main gas stations' tanks to rip off people. At that time I had a 318Diesel that was used with water in the tank and never ran into a problem. And I'm talking years of running on diesel fuel mixed with water.
Seriously, how much water can he get in the tank, at a power wash considering that he already top it off? Better yet OP, ask your dealer but I guess you'll get the same answer.

[Doug Huffman]

Originally Posted by youry

[ ... ] diesel fuel mixed with water. [ ... ]

Sorry, I did not know that American English is not your preferred language.

Immiscible means UN-MIXABLE
https://en.wiktionary.org/wiki/immiscible

[youry]

Originally Posted by Doug Huffman

Sorry, I did not know that American English is not your preferred language.

Immiscible means UN-MIXABLE
https://en.wiktionary.org/wiki/immiscible

Out of habit, my bad.

[Doug Huffman]

Originally Posted by youry

... one pint of water which is mixed with 20 gallons of fuel. That's something like 2% water 98% fuel...

By volume: 1 pint in 160 pints (8 pints/gallon x 20 gallons) is 0.00625 or 0.625%. Not even 1%

[windforce]

Thanks for all the concerns, my friends! The engine runs fine. No CEL yet. Should i add some Redline water remover/injector cleaner? And do a engine oil change?

[regdfry]

For peace of mind add a water remover, like PS Clear-Diesel: here is info from their website.


Clear-Diesel Fuel & Tank Cleaner is an advanced diesel fuel and tank cleaning technology. Water has always been a problem in diesel fuel. But today’s cleaner-burning fuels have dramatically reduced sulfur content and are more prone to water separation, contamination and are inherently unstable. This Fuel Polishing Formula removes water and slime, disperses fuel contaminants and stabilizes fuel during long-term storage. It can be used as a vital part of any preventive maintenance program or for immediate clean-up of equipment or fuel storage tanks. Add Clear-Diesel at least quarterly or as needed.
Benefits

Disperses diesel fuel contaminants
Removes water and slime
+Petrofresh provides maximum long-term storage stability – keeps fuel fresh
Prevents premature fuel-filter plugging
Protects against fuel tank corrosion
Effective in conjunction with Bio Kleen Diesel Fuel Biocide to remove residual water and contaminants during microbial contamination clean-ups
Effective in all diesel fuels, including Ultra Low Sulfur Diesel (ULSD), biodiesel and biodiesel blends
Does not contain alcohol of any kind
Safe for use in all diesel engines
Will not void engine manufacturer's warranty when used as directed

[Pierce330]

Didn't your check engine light turn on?