CSL Tune with EKP Fuel Pump Relay?

[DropTopKingM3]

Yes I know it can back bleed through a not working check valve.
But the problem is not the pump, it’s the signal from dme that’s missing…It does working normal with running engine or with manual inpa activation…

My car has been doing this forever. I replaced the fuel pump 2 months ago and Im still having the same problem. Im currently having my crank sensor, fuel filter, and fuel pressure regulator replaced. If that doesn't work I'm aiming toward a fuel pump relay. The only other thing I can think of is one of the injectors are dirty or one of the rings around them are no good.

I did a search and this plagued a lot of e46 M3s.

[S54B32]

My car has been doing this forever. I replaced the fuel pump 2 months ago and Im still having the same problem. Im currently having my crank sensor, fuel filter, and fuel pressure regulator replaced. If that doesn't work I'm aiming toward a fuel pump relay. The only other thing I can think of is one of the injectors are dirty or one of the rings around them are no good.

I did a search and this plagued a lot of e46 M3s.

Currently my injectors are send away for a service (flow/spraypattern testing, cleaning etc). Even without the start problem, I wanted to do this.
i ruled out the fuel pump, even when I priming manual multiple times I don‘t get a start on first start. Relay seems also ok.

When the fuel injectors come back and the problem is not resolved, I will do some logging during start/crank. Maybe it’s sensor related, but I don‘t think that. Because the fault is too consistent and don‘t throw a single code. But I will solve this problem, only matter of time because it‘s a bit frustrating that you only have 1 or 2 try’s per day for this Problem (only happens when car is cold/parked for >8h)

[S54B32]

My car has been doing this forever. I replaced the fuel pump 2 months ago and Im still having the same problem. Im currently having my crank sensor, fuel filter, and fuel pressure regulator replaced. If that doesn't work I'm aiming toward a fuel pump relay. The only other thing I can think of is one of the injectors are dirty or one of the rings around them are no good.

I did a search and this plagued a lot of e46 M3s.

If someone tracing down a similar issue, since injector cleaning/„rebuild“ I got start every first crank. Before as described above every single time (when cold) 2 cranks to fire it up (or more if the battery was a bit low on power).
Per injector cleaning datasheet the flow rate was not that bad, but spray pattern very bad before cleaning.


edit: nevermind, issue went back after a couple of days…but runs still smoother than pre cleaning.