BMW E30 IGNITION problem

[crossie]

Am still having problems starting my car!

All now wired up correctly but when you turn the key the starter just turns and turns (you don't need to hold the key!)
plus the fuel pump doesn't start.

(fuel pumps both work when you bypass the fuel relay!)

[crossie]

https://www.instagram.com/p/BC5xg0OjPwj ... rossiecars

[Brianmoooore]

What car? What age? What engine? Is this a problem that has developed on its own, or since the car has been worked on?
I need to know exactly what wires are where on the starter motor, and the colours of the two smaller ones, which should be under an outer black sheath.

[Yeti]

fuel pump wont run until engine turns over.they dont prime on ignition. get a multimeter and start checking the wiring going to the starter as there should be a small single wire going to the solenoid on the starter which activates it. there should be a 12v feed going to it and if you say its still running going there should be still a 12v feed in the wire if not there must be a short inside the starter but if so the ignition switch could be fooked inside giving it a permanent 12v feed.

[Brdjo]

+1 on ignition switch... if i see right, your key doesn't go one step back on release, after cranking..??

[crossie]

I spoke to dan last night and we think the wires from the ignition multi plug to c101 plug maybe the problem
As it was turning over even with the starter wire in plugged from the ignition multi plug

History
E30 m3
3 litre engine fitted
Dan wired engine loom to fit
I fitted it all
Never worked so added a wire direct to starter from ignition multi plug and added extra loom for fuel pumps
Which had it all working ran for 3 years

Now trying to get it all to work correctly
Tidy it all up!

[crossie]

The ignition switch worked fine when I had the wire direct
So l am going follow a few wires this evening to check for damage

[Brianmoooore]

I need to know exactly what wires are where on the starter motor, and the colours of the two smaller ones, which should be under an outer black sheath.

[crossie]

Will check these when I get home

[crossie]

Yellow black bottom
Green black top smallest

[crossie]

ignition now sorted thanks to Dan - just got to get the fuel pumps to work as well!

[Brianmoooore]

You say that the pump works if you bypass the relay. The relay is part of the engine loom, so there must be an engine loom or ECU fault affecting the relay's control circuit.

[crossie]

jumped the fuel relay and tried starting the car with no luck!

AHHHHHHH I hate cars!

Any idea where next to look?

Which wire controls the relay circuit?

[Brianmoooore]

Engine ECU controls the pump relay by pulling down one end of the coil. Just a simple wire from ECU to relay.
I thought you said the ignition has been sorted out, and, presumably, you now have sparks. If so, why doesn't the car start if the pump relay is 'jumped'?
Injectors not working?

[pianist]

is there spark? your cps might be dead thus if ecu can't see engine turning it will not turn pump on

[crossie]

Worked this evening

fuel pump wired the wrong way (my own fault)

need to finish re fitting the inlet and a few other bits but should have it out and back on the road Saturday!

Thanks all for your help / ideas!