bmwe21.net forums

No I don't because that's exactly how if set it up and the pump doesn't turn on unless I give the pump a direct feed but that wrong becuase it on constantly then. I need it to turn on when I turn the ignition.

lol still can't believe your struggling with this.. you need a multi meter. find a switched live, and then you can run a signal wire to the relay.

doesnt switch on with ignition on e30s, if it sees a signal from the crank sensor... the ecu switches the live in to the fuel pump relay, which in turn puts out the live down pin 13 on cranking..... the one on the front pulley.... is it plugged in? have you mixed the plug up with the one for the cylinder recognition plug...... the one that intersects one of the plug leads? the plugs for both are on a bracket on the front of the inlet manifold. they will plug into each other... so check!

have you distrubed the crank sensor at all? if you have the gap needs to be very precise. 0.75mm if memory serves.... too far away and the wave form signal is too small, too close and the signal is too big for the ecu to make sence of.......

have you got a spark on cranking too?

On friday after fitting the new fuel pump and re piping it with new pipes. I tested it and thank god i was getting petrol to the front of engine so that was cleared. i turned the car on and then simply gave a live to fuel pump and it started after a couple seconds i left it running for a while but still held the live to the fuel pump because otherwise it wasn't turning on. after a couple minutes of the car on i had a big smile on my face i turned the car off and thought id try firing it up again but this no luck after sooooo many tries.

What could be the problem now? I will check the crank sensor and see if that turns the fuel pump on.

if you were nearer id come and look at it............. but your not!

right looking at my e30 wiring diagram......


also the green wire at pin 7 on the c101 plug have you got this going to a ignition live (green wire) on the e21 engine loom. this is one of the start input wires and is also the live to the coil.