325 NON STARTER

Hi,

Your test of supplys at the coil is ok. The coil should be earthed through the ECU to induce a spark. If you put a volt meter on the neg side and crank, what do you see? The problem you have here is that a meter can not read fast enough to capture the switching action. Since you have tried a new coil and you have a supply then the fault must lie with the earth side of the circuit. Either you have a wiring problem or the ECU is not switching the coil to earth. With the latter, this could be for any number of reasons. You should check the wiring from the coil to the ECU and ECU supplys and earths.

What way were the sensors checked?

If you flick the starter ie. just barely enough for the engine to jerk and listen, can you hear the fuel pump run?

If you switch the key to the run position can you hear the pump run?

Do you have supply at both sides of any or all injectors with the key on?

Do you have a 5v supply to the coolant sensor (blue one with 2 pins)?

Alan

alan,

had a quick look at car thisafternoon but due to rain didnt get much done.

we confirmed 5v on coolant sensor, checked two injectors for voltage but none present(is this due to engine position?) couldnt gain access to others. traced green wire on coil back to ignition barrell switch, wire continuity ok-insulation ok. could the ignition switch be at fault?

can u advise on how to check ecu earth is ok and how to check if ecu neg supply ok(plus 12v present on pin 35)

any info welcome, many thanks.

alan,

have been having a look at the car today and can now confirm we have voltage to the injectors with key 'on' and when engine cranked. removed position and speed switches measured resistance on pin 1 and 2 found to be 860ohms which is within spec given in haynes manual. actuated swithes while measuring on pins 1 and 2 and confirmed resistance changed when a metallic object is passed over the sensing head of the switch.

a few questions; the green wire from coil traced back to ignition barrell, could this switch cause a problem, and will this wire then go back to ecu?

traced injector supplies from battery through relay and to injector and then back to pins 14 and 15 on ecu, how can i confirm ecu is switching to earth (or neg)?

and can u tell me what the unit above the glovebox is which has an ecu type connection?

at this time we have;

5v on coolant sensor, voltage on injectors, speed and position sensor resistance in spec and continuity to ecu pins ok, coil primary and secondary resistance in spec, but still no spark from plugs!!!!

any info appreciated!

alan,

i have checked the car for the things you have suggested, all seem ok but still no luck. have heard on the grape vine that the tag on the fly wheel  which the position sensor looks at within the bell housing can come off. this then causes no signal from the position sensor.

there is supply to the injectors but they cant be heard to 'tick' when engine cranked.

fuel pump in tank and secondary fuel pump in engine bay run when engine cracked

have hand cranked the engine and found what looks like a pin laying horizontal within a circular recess on the flywheel. is this what the position sensor looks at or is there supposed to be a raised tag which may of fallen off?

please advise, if this doesnt work its going in the river.

cheers.

well guys i'm pleased to say she is running again, after a visit to bmw and a supposed bmw specialist who were'nt much help -we have sorted it ourselves. it seems the tag has somehow came off the flywheel, therefore sensor not sending signal to ecu and no spark etc!!!! we have a secondhand flywheel on the way and will put in a new clutch while it's all in bits. we have decided to turn the car into a bit of a track machine (as a new e30 325 has been purchased)which brings me onto my next subject; TUNING, anyone tried any tuning on a e30 325i and what gives best bang for ur buck?

cheers for the replies and tech help.