E39 525D Starting Problem!!

[chazlee123]

Hello everyone..

Browsed these forums for quite some time so I thought it was time to sign up..

Anyway iv got a problem with a beemer..

Iv got an intermittant starting problem..

Its my mums and she kept moaning that it wouldnt start some mornings first time.. I went out to it after she moaned and it would start straight off.. But my dad went out just after I did and it wouldnt start.. Weird..

Anyway I had a closer look, the pump isnt buzzing when you turn the ignition on, only sometimes, when you hear it buzz you know its gunna start..

But now it wont buzz at all, I cant get the pump to kick in..

Pump at fault? Or could it be something like the pump relay? Immobiliser etc..?

Also noticed it doesnt want to rev up when its cold.. And if you rev it right round its restricted to 4000 RPM.. If you hold it there after about 5 seconds it will clear, a bit puff of black smoke out the back and it will rev right round to the limiter but when you let off and let it idle when it reachs idle speed it starts to splutter slightly then it clears again..

Took it up the road when I eventually got it to start and its flat as a pancake, its an auto and when its gets into 3rd its sitting at 4000 RPM for ages before it will change up, and when you kick down, it changes down but doesnt pin you like it should..

After all this I had the filter off and emptied it and the diesel came out black! So as a temporary measure I reversed the filter and blew it all backwards to get all the crap out, the diesel coming out is now clear, it seems to be a lot quicker and happier to pull but still not right..

I come home parked it up, went back to it 10 mins later and nothing, cant get the pump to kick in..

I had the pump under the passenger seat out, wired it to a battery and it buzz's away and pumps fuel like mad..?

I took the fuel pipe off just BEFORE the middle pump and the rear pump in the tank is working, there seems to be one each side? Dont know if they are both pumps? But they both are buzzing anyway..

I put the middle pump back on and it started again?

I pulled it forward 10 yards, stopped it.. Went to start it again and nothing..

But sometimes the pumps will kick in and sometimes not, I dont think it is the pumps at fault.. I think something is stopping them from kicking in..?

Any advice? Its driving me mad!!

Cheers,
Chaz



EDIT;

Would it possibly be the crank sensor? If so where is it located on a E39 525D..?