XSeries-forum

Hi all i am the now not so proud owner of an x3 3.0d, to be fair its been reliable for the last 10000 miles since i bought it.
It all started with my dde light coming on a couple of times while driving from work, then on the way to work it came on and would not go out unless i deleted the code with my scanning tool. I managed to drive to work with the scanning tool on my lap deleting the code everytime the light came on thus keeping the car from conking out. A day later trying to limp the car home it completely died going down a hill and came with a second code 4B90.
I have changed the throttle body and egr unit and solved the first issue but i am very stuck on the second.

So far i have found that fuel is getting to the pipe that connects to the fuel rail but will not get past the fuel pressure regulator unless i loosen it from the back of the rail ( i have changed the preesure regulator but still no joy,
with it loosened fuel fills the rail and fuel pipes for each injector but will not fire or try to.
Any help of where to start would be great ( could it be injectors failing ) ? i am at a loss thanks

Fault code 4B90 -RAIL PRESSURE CONTROL AT START,,,,,,, when car is cranking fuel pressure bleeds off via broken jammed needles in injectors so will not atomize the fuel spray at the injector tip,,,did you not get injector codes prior???...you should have done or you would have done on live diagnostics...its one or more of your injectors gone..had this before and it was only one injector..

Hi i did not have any fault codes for injectors before only had the two codes mentioned. Would i be able to get the live data by cranking it over even though it does not run ? I just cannot understand why the fuel pressure regulator will not open to let fuel into the rail. thanks for your help i will try an look at the injectors

You only mentioned one code....no cranking it over will not give you live data,the fuel pressure regulator is opening, but as one or more of the injectors has gone a message is sent to the ECU via the injector/injectors telling it to close...."Hello Im not working so no fuel required"

Hi marti many thanks that will be my next port of call then injectors

What was the outcome with your non-starting engine, did you get it resolved?