325i intermittent starting issue

[pimp_mobile]

Hi All,

My H reg 325i is struggling to start/ turn over. When it does start it runs absolutely fine. I suspect its either the fuel pump relay or if it has one the starter relay. Are both these situated next to the DME relay?

Does anyone have the part number for these?

Cheers

[jamie325isport]

If its just turning the starter motor over it wont be anything to do with your fuel pump. Not sure if theres a starter motor relay. It could be either the starter itself or the ignition switch. To test the switch turn it to live take a piece of wire and go from the battery directly to the starter motor.

Cheers Jamie

[pimp_mobile]

When its not working the engine doesn't even turn over. All the lights come on, on the dashboard. Usually fires up second time rather than first.

Recent work has seen us service the "firing cog" on the starter motor, and change the fuel pump which had failed.

Instinct makes me feel its either a solonoid or a relay sticking.

[jamie325isport]

Have you had a mate give the starter motor a bang with a bit of wood to try and bring it to life? Does it try and do anything? Does it click, do the dash lights dim slighty?

[pimp_mobile]

Didn't get round to banging the starter last night... after 30 minutes turning it on and off it decided to fire... I did remove and shake the Blue and Orange relays next to the White DME relay. Not sure what the other two do.

I didn't notice the dashboard lights dimming, so my guess is that it wasn't even letting power through to the starter.

My Bro's going to take a look on sunday but just trying to see whether it could be sorted before then.

[jamie325isport]

If its not letting power to the starter I would think maybe the ignition switch. I had it with a VW years ago the switch worked fine until I would try to start the car. To bypass it I had to turn the ignition to live then pop the bonnet get my bit of wire and go from the live on the battery to the live on the starter motor and it use to start straight away. Being a 325 you wont have the battery under the bonnet but you do have a live point by the battery tray. Give that ago. Try it a few times to make sure its that. If it doesnt start then its probably the starter motor.

[pimp_mobile]

I take it the live on the starter motor is the big red lead.

Cheers for your help... I might give that a go tonight if I get chance.

[jamie325isport]

Yes mate thats the one. Worth a try. All the best

[Brianmoooore]

If its not letting power to the starter I would think maybe the ignition switch. I had it with a VW years ago the switch worked fine until I would try to start the car. To bypass it I had to turn the ignition to live then pop the bonnet get my bit of wire and go from the live on the battery to the live on the starter motor and it use to start straight away. Being a 325 you wont have the battery under the bonnet but you do have a live point by the battery tray. Give that ago. Try it a few times to make sure its that. If it doesnt start then its probably the starter motor.

This is a BMW, not a Ford or some other mass market sh*te! BMW kindly provide you with a diagnostic socket, on the top front of the engine.
Remove the cap and carefully identify pins 11 and 14.
Link them together with a piece of wire, and the starter motor should turn the engine. If the ignition is on, it should start.

[pimp_mobile]

Cheers, I don't suppose the pins are numbered are they.

[Brianmoooore]

They are numbered, but it's not immediately obvious for some pins which numbers refer to which.
Identify all of them, and mark the two you need with white paint or tipex.
Only autos have a starter relay, and it's nowhere near where you have been looking!

[pimp_mobile]

Cheers Brian...

My brother looked at the wiring diagram and realised it didn't have a relay. We've replaced the starter motor, though now its struggling to fire up. It will eventually fire up and runs fine once it does. I've eyeballed the wiring from the starter and everything seems to be connected. Any clues, it tends to be worse when its cold or has been stood a while.

[Brianmoooore]

Pull out the fuel pump relay (orange, four pin one, under the cover on the air filter bracket), and link together pins 30 and 87 of its base with a short piece of wire. This should make the fuel pump run continuously.
Start the car from cold with this link in place, and see if it improves things.

[pimp_mobile]

Thanks...

To complete my week the clutch has now gone... Groan...

[pimp_mobile]

Clutch sorted now, and we've swapped the relay to a new one, which has made a small difference, but it still seems slow to fire. Going to grab some injector cleaner next, but any other ideas as to what the issue might be. As ever when it starts it runs fine.

[pimp_mobile]

What does the blue relay do, next to the fuel pump relay?