resunoiz

I have a very weird problem, from a year from now.
While driving, at every speed, in every gear, with every weather...car randomly starts hiccup like no petrol is coming to the engine. Pushing down gas pedal I can hear air (I think so) coming into the engine, but no accelleration or other. Car inevitably after some seconds shuts off.
The scary thing is that even if at high speed, it shuts and doesn't restart with cars' movement, like there is no petrol. A very scary thing when it happens.

NO engine failer indicators, NO error in the screen, NO errors in the fuel pump from diagnosys in BMW.

I'm lucky my car is converted togo with CNG (methan) so I've experienced this thing only in few moments, for example when I can't fill methan. The car instead runs like a charm with CNG, no problems at all.
This summer, going to BMW Next 100 festival in munchen because in germany I had no chance to fill CNG I had to experience this issue a ot of times, in motorway too with no chance to restart the car while driving. Not a beautiful thing.

The fact is that in BMW they don't have idea of what can be: no errors in memory, so it can be done only "blind spare parts changes" and it is not the right thing to do obviously.
They told me maybe there will be some wire interrupted somewhere in the ignitors, but thy're not sure. And changing all the car's wiring only for a blind test is not suitable.

Have someone experienced an issue like this?

When the car shuts off, is like a camshaft sensor failure (experienced it with Z3) but the strange thing that it happens ONLY going with petrol, not with CNG. So I think I can exclude camshaft sensor and sensor like this, seems something related to the fuel only...

doctorbubba010

I am thinking it could be a relay. Im not the smartest cookie, but heres what I found RealOEM.com - Online BMW Parts Catalog

E60I

My car shuts off three times within three months "while driving on the freeway". After putting back the old fuel pump (with 80k miles when I replaced it as preventative maintenance) and tightened up one of the hoses (where the MAF sensor is located), the car has been running normal ever since. I am putting on another new genuine BMW fuel pump this weekend just have some peace of mind...

I think my last new fuel pump (2nd one) lasted less than 40,000 miles because I let the "You are low on fuel message coming on once too many times". That could have been the cause for a premature failing fuel pump.

resunoiz

...but you had some warnings from that fuel pump?

mine none on screen and on diagnosis memory in BMW. that's the weird thing

resunoiz

what relay?

richie281vn

I got the same and it was the crankcase sensor failure. Replace the sensor and it works like a champ

resunoiz

unfortunately, NOT in my case. had this issue with Z3

when driving with CNG fuel (90% of the time) the problem is not present. Is fuel-related and does not "shut off" the car, simply no petrol arrives. Electrically the car remains active.