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james k taylor

james ... 5/8/2011

1999 BMW 328is Base 6 Cyl 2.8L


Engine miss fires, water is coming from the exhaust . engine check says fuel trim malfunction(bank 1)

1 Answer

Spoon Sports

Spoon Sports 5/9/2011

It's that time of year when we see a lot of water vapor out the tailpipe. It takes longer to disappear in the winter as it takes a while to heat up the whole exhaust system. It's not something to worry about, as long as it's white and eventually disappears, as you have been observing.

P0170 - Fuel Trim Malfunction (Bank 1)

Possible Symptoms:

Check engine light on
Engine stall
Poor gas mileage
Black exhaust smoke
Engine hesitation or misfire

Possible Causes:

Dirty or defective MAF sensor
Vacuum leak
Defective fuel pressure regulator
Defective O2 sensor
Oil contamination in the cam/crank sensor wiring or MAF/O2 sensor connector

Possible solutions:

Clean or replace MAF sensor
Replace fuel regulator
Replace damaged or cracked vacuum hoses
Clean cam/crank sensor wiring or MAF/O2 sensor connector
Replace O2 sensor


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