Non start

[BMW_E30vert]

1991 e30 325i auto
M30 conversion using m20 wiring loom

Car cranks but not starting, when I turn key I can't hear the relays/Icv/abs clicking.
If I jump the dme relay pins all the above click
If I jump fuel pump it works
So it's not getting no spark or fuel
Ground strap to engine attached
This wiring loom worked with the m20 auto previously in car
I'm pulling my hair out trying to diagnose this
Is it possible it could be crank position sensor? old engine is gone so can't use the known good sensor off that

[Brianmoooore]

For no spark and no fuel pump, the crank sensor is the prime suspect, although, on an installation that has never run, there are other possibilities, of course. Your testing to date has eliminated many of those, though.
Have you tested the resistance of the sensor? There should be a resistance of around 540 ohms across two of the pins, and open circuit across the other two combinations of pins. Wriggle the wire a little at the sensor end when you take the resistance reading.
An incorrect reading will prove duff sensor, but a correct one unfortunately doesn't prove that it's good.

[BMW_E30vert]

Thanks Brian I haven't checked cps resistance yet this will be my next step, will a non working sensor cause the relays/abs not to click with ignition on?

Also we're is the best place to get a sensor Euro/gsf or best to get from dealers?

[Brianmoooore]

Non working CPS won't affect anything in any way until the crankshaft turns.
It's a fairly simple device, not 'calibrated' in any way, so aftermarket should be OK.

[BMW_E30vert]

So what can cause the relays/icv/abs not to click with ignition on? I've tried a known working dme relay but this didn't work but jumping pins 30/87/87 gets them to click

[Brianmoooore]

Sorry, read your OP wrong.
Turn the ignition on and pull out the DME (probably white) relay. As you pull it out it should click, and click again as you push it back in. If it doesn't, then the ignition 'on' signal is probably not reaching the ECU.
The DME relay has five pins. Are you sure that it's in the right socket? The one with wires to five pins.

[BMW_E30vert]

Dme is definitely in the right location, it doesn't click when removing or pushing back in but if I jump the pins 87a 87b and 30 icv starts buzzing so does the abs pump like what would normally happen if you turned ignition on.

How would I supply or rectify the ignition 'on' signal?

[Brianmoooore]

Check that there is 12 volts on the + terminal of the ignition coil with the ignition on, preferably with a 12 volt bulb connected between the + terminal and a good body earth.

[BMW_E30vert]

Did bulb test and there is no 12v at +terminal on the coil with ignition on

[Brianmoooore]

Did bulb test and there is no 12v at +terminal on the coil with ignition on

Then, somewhere between the ignition switch and the engine loom, the 12 volts + ignition switched live wire, plain green, has a break in it.
First thing I'd do, is to connect a wire from the coil + terminal directly to the battery + terminal and try to start the engine. It should run, and confirm that all that is wrong is one simple wiring problem.
Disconnect the C101 engine loom plug, and check for 12 volt with the ignition on on pin 7 of the C101 on the car body side. If it's missing here, go back to the immobiliser socket behind the glovebox. This is a two pin socket hanging from the loom at the top with two plain green wires, which should either have a plug fitted into it with a short loop of green wire, or a plug with wires going to an immobiliser (or two). Check for 12 volts at the pins of this plug with the ignition on.

[BMW_E30vert]

Direct wire to coil did not start car, I then moved a few wires about under glovebox(was looking for the green wires)and the car fired up.

I then tried to turn it off and it wouldn't even after I completely removed the key, I then removed the screwdriver that was holding throttle open and engine turned off.

what I failed to mention is the car has a laserline 986 immobiliser(although this was disabled when the m20 engine was in the car) I found the green wires in glovebox area and sure enough a wire was spliced in.

Removed the immobiliser wire and connected plain green so now relays get power with ignition on and I have 12v at coil but now I have no fuel coming haven't checked spark yet.

Could this immobiliser also cut fuel pump?

[Brianmoooore]

Could well do. Most aftermarket immobiliser have provision for two separate immobiliser connections, so it might be connected to the fuel pump. We already know it's not affecting the cranking circuit.
Fuel pump wires are green/purple, so look for connections to a wire of this colour.
Unless you are thoroughly familiar with your car's wiring, don't assume that there's only one immobiliser. My record is three, all long abandoned.

[BMW_E30vert]

Ok checked wiring of immobiliser and i believe it's The only immobiliser, removed wires that were spliced in but was left with three wires which were going into speaker footwell I cut these anyway and removed immobiliser.

It still wouldn't start so I checked and moved about crank sensor wiring(while doing this noticed some of the plastic sheath was gone exposing the wire) checked for spark and fuel which was now present and turned key to hear it fire up.

But 15mins later when I tidied up the wiring it wouldn't start no fuel or spark

I'm hoping it's crank sensor I've bought a second hand known working sensor so fingers crossed will report back

[Brianmoooore]

Beginning to look like the crank sensor might be faulty as well as the immobiliser problem.
Wires going to the speaker are probably the connections to the central locking, but there should only be two of them. Fuel pump wire goes down the left hand corner by the speaker.

[BMW_E30vert]

Update:

Second hand sensor fitted and it fired right up

Owe you a drink can't thank you enough brianmoooore for your help cheers buddy