e34 not starting

e34bears · Feb 27, 2014

hi chaps some much needed help wanted , my 1988 535i e34 manual has just decided not to start , the car has been running absolutely fine and has always started first turn of the key until this week ...... i only use the car occasionally as a second car so it spends most of its time in the garage , last week i went out to the garage connected the battery turned the key and she started sweet as always , after carrying out a few jobs which was changing both rear sub-frame bushes and fitting a new cd player i took her for a short ride and all seemed fine ,i noticed the fuel light was on so put some fuel in and parked her in the garage as usual switched off and disconnected the battery as usual , a few days later went out to start her and she turns over but wont fire???? seriously wierd as all was fine a few days earlier , for some strange reason now on the dash display comes up with oil pressure fault see owners hand book..and the eml dosent light up when the ignition is switched on all though i cant remember if it did before

the things i have checked so far are
all fuses --seem ok
power to fuel pump---ok
i bridged the fuel pump relay and disconeccted the fuel feed and fuel is being supplied ok
removed plug and crank...no signs of spark and plugs do not smell of fuel ?????

seriously baffled as to how it could develop a fault from being parked up as per usual with no power supply???and why its saying oil pressure fault

the only thing i can think is maybe by re-attaching the battery terminal has caused something to blow , but saying that all fuses i can see seem ok , could it be a relay or eml unit???
any help much appreciated

TheEnd · Feb 27, 2014

The oil pressure warning could just be from the cranking not turning it fast enough to build enough pressure.
For another test of the crank sensor, check to see that the fuel pump primes when you switch the ignition on (1-2 second buzz) and then stop, and when cranking again, it should restart.
If it doesn't restart, it might be the crank sensor. Also look to see if the rev needle moves when cranking, but often cranking speeds are too low to register. You could also see if it pumps fuel when cranking to show the pump restarts after the initial priming.

If it doesn't get a crank signal, it doesn't realise the engine is turning over so doesn't do anything else.

e34bears · Feb 27, 2014

hi thanks for the reply , why would the crank sensor become faulty all of a sudden without any prior warning or rough running?? is there any way to check it with a multi-meter? cheers

TheEnd · Feb 27, 2014

I'm not sure if you can check a crank sensor, but you can try.
You'd need to tap into the signal wire from it and look at the readings when cranking. It should make a pulsed waveform, or you can look for resistance, which should be somewhere between 400-1000Ohms, I'm not sure of the exact figure, but in that region

e34 not starting

Our Vendors

Top Contributors this Month

Recommended Communities