Turning over but won't fire up!

[Ravenelli69]

Picked up a 325i convertible in need of repair last week. There was no key so I got one off bmw and it thankfully worked! Car is trying to start but there is no noise coming from the fuel pump. I swapped over a working fuel pump to see if that was the problem but no joy! Before you ask there is fuel in it and there are sparks coming from the spark plugs. I have also swapped over fuel pump relays and changed fuses but still no joy! Could this be the crank shaft sensor - what ever that is?? Is there a way of testing it before taking it out? Also, if it is that whats the best way to remove this - as the wire seems to be buried behind a load of bits - does the radiator have to come out? Would an immobiliser allow an engine to turn over but not start? Any advice appreciated but bear in mind I'm not electrically minded!!!!!!!

[E30-Addict]

There is a magic diagnosis table on the wiki section somewhere

It takes you step by step to narrow down exactly your car issue

[Grrrmachine]

There is a magic diagnosis table on the wiki section somewhere

http://www.e30zone.net/e30zonewiki/inde ... oubleshoot

[Ravenelli69]

Thanks for that I will keep you posted on progress!

[Ravenelli69]

Update -

- I have bridged the pin 30 & 87 of the fuel pump and thankfully it's working.

- I have tested pin 85 & 87 with a bulb and they are also fine
- I I have also bridged the DME relay (30, 87 & 87) and it is turning over but failing to start!

- I tested the ECU and there is no power to the pins 18, 27 & 37?????

When I try to start it there is no sound coming from fuel pump (only when I bypass it)

Could this have something to do with an immobiliser? I was informed by BMW that the immobiliser was built into the new key?

Baffled - although at least i've learned something about electrics!!!!!

[Speedtouch]

http://www.e30zone.net/e30zonewiki/inde ... ion_Sensor

Have you tried disconnecting and reconnecting the battery? And what age is the car, and does it have the OBC, since this has an immobiliser ('CODE' function) built in.

[Ravenelli69]

It's a 1990 model. I tried disconnecting the battery but no joy. It has an OBC so what do I do with that?

[Speedtouch]

RTFM!

http://www.e30zone.net/e30zonewiki/inde ... ction_Book

When you bridge the fuel pump relay and get the pump working, does the engine then start?

[Ravenelli69]

It's turning over but not starting!

[Speedtouch]

If you're getting air, sparks and fuel, then it should start. Try spraying some carb/brake cleaner down the throttle body while you crank the engine over.

[Ravenelli69]

Will do!

[Ravenelli69]

In relation to the OBC I had a look at the technical section of the website and it says that three attempts at putting in the code will stop it from being started. Could this be part of my problem when trying to start it normally (not bypassing). How do I go about resetting the code - or is this something I need to get off BMW?

[Speedtouch]

I think that disconnecting the battery and leaving it for a while resets the code/immobiliser.

[Brianmoooore]

I think that disconnecting the battery and leaving it for a while resets the code/immobiliser.

Disconnecting the battery for half a second resets the CODE immobiliser. Not the most effective theft deterrent, but only marginally so compared with all other E30 immobilisers I've seen, except those fitted with M5x engines.

Connect a piece of wire from the battery + terminal to the coil + terminal, leaving all existing wires connected, then try to start it.

[Ravenelli69]

I'll check that first thing and revert back - hopefully it starts!!!

[Ravenelli69]

Ok bridged across and nothing! took off plug to coil and couldn't see a spark! I have a working coil in another E30 one so i'll swap it out and try it again!

[Ravenelli69]

Swapped it over but no joy. The engine is turning over but I have no spark! I have pins 30/87/87 bridged to get pump running but still nothing. I have also swapped over a crankshaft sensor (old one was badly damaged) from another e30 as it needed replacing. Confused.com

[Brianmoooore]

Before you ask there are sparks coming from the spark plugs.

We can only diagnose on the info. that you give us!
Do you have fuel pump activity and/or sparks when you crank the engine?

[Ravenelli69]

Fuel pump only kicks when bridged. There were sparks when I first started but no sign of any now from leads or coil when turning engine.

[Grrrmachine]

If you've got no fuel or sparks, then the replacement CPS you fitted is duff, or you fitted it wrong.

[Ravenelli69]

I'll check it again tomorrow and failing that get a new one! Thanks for the advice I will let you know when it's up and running.