Every time I accelerate onto the freeway, the engine cuts out, EML light comes flashing on, and enters limpmode. It then runs rough and surges rpm's until i turn off car and then back on. Started after I was getting p0171 & p0174 codes. replaced vacuum hose, MAF, fuel pump, O2 sensors.
eml light with p0171 on 2004 BMW 325i
by Visitor in Livermore, CA on June 28, 2010
ANSWER by Chow , June 29, 2010
It appears those codes are exhaust too lean faults Do you have an aftermarket oiled air filter? Is the airflow meter fitted backwards? I would be checking for an intake leak Few common places are: -The intake bellow develp cracks and splits -The cyclone to dipstick hose splits at the very top near the cyclone -Under the fuel rail/intake manifold cover is a long hose reaching along a few cylinders, it is an insulated hose which has has gone a bit hard and crumby, this can also spring an air leak sometimes. There are many other possibilities, best to have your local mechanic to check it, which can be found in the "find a shop" tab above