Starting problems

[Jim]

I’ve had a starting problem on my 89 325i for a while, its very intermittent but becoming increasingly worse.
I would turn the key and nothing, but it will start every time if I bridge the starter pin no.11 on the diagnostic socket which tells me the battery and starter are working fine.
I’ve also changed the ignition switch and cleaned most of the connections but still have the problem.

Any ideas?

Thanks in advance

[magpie]

have you checked the connections are tight on the starter motor and that your earth strap from engine to chassis isn't corroded/snapped in half ?

[BenHar]

If it works from the diagnostic socket the connections are probably OK.

Most likely cause is a worn ignition switch.

Ben

[Jim]

cleaned all the starter connections and replaced the ignition switch, earth strap and battery

Jim

[Billwill]

If this is an automatic then there is a starter relay....manual does not have a relay I believe.

You will need to trace the Black/Yellow wire going from ignition switch to the solenoid...maybe run a section of wire seperately from the ignition switch directly to the solenoid as a temporaly measure to see if the bug disapears.

[Brianmoooore]

If this is an automatic then there is a starter relay....manual does not have a relay I believe.

You will need to trace the Black/Yellow wire going from ignition switch to the solenoid...maybe run a section of wire seperately from the ignition switch directly to the solenoid as a temporaly measure to see if the bug disapears.

Correct, but if it is an auto, the most likely cause is a misaligned gear selector lever.

[Jim]

sorry guys its a manual

Jim

[Brianmoooore]

If you're sure it was born a manual, and are sure the ignition switch is OK, the joints in the cable are the places to check. There's a plug and socket, part of a multi pin plug and socket, which should be clipped to the steering column half way down, where the black wire soldered to the ignition switch becomes black/yellow.
There's a single pin plug and socket in the black/yellow wire above the glovebox, where the starter inhibitor would plug in if it were an auto. Check that this is plugged together properly.
Finally, there's the 20 pin C101 engine loom plug and socket, next to the fusebox. Check that this is fully together, with the locking ring turned as far as it will go.
There's also the possibility of an alarm/immobiliser connected into this wire somewhere, whether you know of its existence or not. Alternatively, there mat have been an immobiliser removed at some time, and the wires not joined back together properly.

[Jim]

If you're sure it was born a manual, and are sure the ignition switch is OK, the joints in the cable are the places to check. There's a plug and socket, part of a multi pin plug and socket, which should be clipped to the steering column half way down, where the black wire soldered to the ignition switch becomes black/yellow.
There's a single pin plug and socket in the black/yellow wire above the glovebox, where the starter inhibitor would plug in if it were an auto. Check that this is plugged together properly.
Finally, there's the 20 pin C101 engine loom plug and socket, next to the fusebox. Check that this is fully together, with the locking ring turned as far as it will go.
There's also the possibility of an alarm/immobiliser connected into this wire somewhere, whether you know of its existence or not. Alternatively, there mat have been an immobiliser removed at some time, and the wires not joined back together properly.

Thanks for your advice Brianmoooore, Yeah it’s an original 325 sport manual I’ve owned for over 10 years with the standard BMW alarm and immobiliser fitted back in 1997. Its only started playing up the last year or so, I don’t use the car much so its probably just a corroded connection somewhere. I will check the connections you’ve mentioned at the weekend.

Thanks for the help

Jim

[Brianmoooore]

Very unlikely to be a 'corroded connection'. It isn't French!