Hey I’m new to the forum searching for some advice. I’ve got an 04 Z4 2.5i. Have been struggling with a long crank before start. Have changed 3 different fuel pumps and a dealer ordered filter. Problem I consistently run into is when priming car shoots up to operating pressures and seemingly looses it in the same moment. I’ve pulled the injection rail and none of the injectors are leaking. As you crank the engine fuel pressure builds and will eventually start seems to run fine after that. Looking for any advice someone could give.
Z4 long crank
- Thread starter TT2017
- Start date
Duff or failing camshaft sensor will cause long cranking, found that out when I forgot to reconnect mine after I unplugged it to do some work in that area. Car did start with it disconnected but crank time was extended. Plugged it back in when I spotted it disconnected and starting was restored to first turn of the key. Fuel pressure you have dosn't sound right, could it be the actual pump or maybe an EWS problem not releasing the fuel pump like the starter motor?
Haven’t done any recent work in that area but I’ll look into a cam sensor. No CEL would have thought that would have popped on. Thought about fuel pump relay and EWS no one has a proper location of it that I could find. Have had the trunk apart and haven’t been able to spot it.
colb said:
Check cam position sensors no luck there. 2 of the fuel pumps have done the same thing one from a local parts store the current one is a Delphi from FCP. New filter from a dealer. When you initially turn the key on it jumps to 50psi and drops within seconds. Makes me feel like there’s a leaky injector which I haven’t seen after pulling the injection and doing testing. While cranking you can watch the fuel pressure climb until it finally starts runs perfect normal when it does start.
