p0056 code after recent PM work, stalled then towed home
 

I recently changed the VCG, fuel filter and transmission fluid and filter. My wife drove about 30 miles, then the engine died on the highway could not restart it then had it towed home. I just read the code p0056, only thing I can think of is I cleaned the wiring for precat O2 sensors with a rag since they had oil from the leaking VCG. The x5 was running perfect before, it was all preventative maintenance(PM). I test drove afterwards and everyting seemed fine. She drove it the next day. Would the x5 run if the blue and black lines , intake and return lines at the fuel filter were mixed up? I just got home and will troubleshoot in the AM. AnyiIdeas?

if the lines were switched at the fuel filter it would crank but not start.

Thanks, I went out today to try and start it and it only cranks but no start.. I checked the fuel pump #47 fuse since I pulled it to relieve the fuel pressure(cranked motor and let it run) before the filter change.

Just connect a fuel pressure gauge at the fuel rail and see if you have pressure with KOEO (Key on engine off). If you don't that's your problem.

That was my first thought but I don't have one but can go and buy one at Napa. They are the only place around within an hour drive. I was going to try starter fluid then go from there.

It just so happens UPS just delivered my new OEM fuel pump from OEMbimmerparts. Another PM item. Napa has a fuel pressure tester for $56 and it's a 45min round trip drive. I think I will swap the fuel pump but the tank is at 1/2 full. I've read it should be 1/4 or less anyone have experience changing the pump at other than 1/4 or less?

I'll done, a fuel pump change at 3/4 tank. Get some good gloves that won't fall apart when they are immersed in gasoline. Shouldn't take but 20 minutes to remove the old and put in a new pump. I think there is only one fuel line connector at the pump. The two lines that you spoke of are at the fuel filter, and yes if you got it backward, the engine is not going to start.

The P0056 DTC is for a heater control, that will not prevent the engine from starting.

Thanks for your replies, the return hose had popped off since I reused the old broken clips, had to go to the autoparts place and get some new ones. Four hours later and I'm done.

Yeah I have done it at 3/4 tank no worries .