[bitmonkey]

Hello everyone,

I've lurked this forum a few times in the past, but this is my first post.

I have an E36 M3 (the 3.0 made I belive from 1994-1995). The other day the car would not start, I've done some digging today and here's what I've found so far:

Here's the view of my fuse and relay box from the front of the car:

The DME relay as labelled has been tested and is OK, when 85 and 86 are energized 30 is continuous with both pin 87s - see below:

There is no power at the fuel pump, and indeed none at fuse 18 (for the pump) so it must surely, if the DME relay is working, be the fuel pump relay. Therein lies the problem - I can't find it. The Bentley manual says the fuel pump relay is a 4 pin bosch like the orange relays labelled in the first picture. The bentley manual says the fuel pump relay is to the left of the DME relay as you look at the car from the side leaning over the fusebox, so in this picture:

the dme relay is the white one and according to the manual the fuel pump relay should be below it in the picture, between the white one and the earth strap - instead, there are a pair of small half-size relays there like this:

Here's another view over the side of the wing showing the DME relay arrowed and the two small relays to the left of it (there are also a pair of identical relays to the right of it)

To make it clear - in the picture below there are 4 orange relays (labelled by white arrows) which are of the type the manual says is used for the fuel pump, I have tested all four of them and they are working fine, but I suspect they are for other things and have nothing to do with the fuel system.

I can only presume the bentley manual is referring to a later model or something, since mine is clearly different.

Assuming I know the DME relay works and that fuse 18 doesn't go live when the key is turned in the ignition I think I can safely say the next step in troubleshooting this is to find and test the fuel pump relay, but I can't find it, so has anyone any advice for me here, or hopefully someone has seen this type of fusebox before and already knows which relay it is?

Thanks

Paul

 

[thegoodbadandugly]

Just a quickie, has the car got an alarm system that may be cut into the fuel pump circuit to provide immobilization?

 

[bitmonkey]

Just a quickie, has the car got an alarm system that may be cut into the fuel pump circuit to provide immobilization?

Hi,

Thanks for replying. I recently had a guy I know remove the alarm for me as there was a problem with it, I do suspect this problem might have something to do with him, so the answer is no, there is no immobiliser on it, but he might have screwed up some wiring somewhere while he was removing the alarm.

Paul

 

[gildersol]

As far as I remember, the relay you've marked as being the fuel pump one is the correct one. You can short pins 30 and 87 in the base with a piece of wire to power the pump

 

[bitmonkey]

As far as I remember, the relay you've marked as being the fuel pump one is the correct one. You can short pins 30 and 87 in the base with a piece of wire to power the pump

Hi, the relay I've marked (with the yellow arrow and pink label) is actually two relays, each have pins 1, 2, 3 and 5.

Is there any reason why there would be two relays rather than one?

 

[gildersol]

Sorry, even though you posted really clearly, I still didn't read it properly:embarrassed. I've not seen that setup before. I'll have a look and see if I can find out.

 

[Ronnie]

Hi, the relay I've marked (with the yellow arrow and pink label) is actually two relays, each have pins 1, 2, 3 and 5.

Is there any reason why there would be two relays rather than one?

I've never seen that before? :confused

Here's what is usually there, http://www.bimmerforums.co.uk/f17/1994-e36-325i-relays-fuses-fusebox-location-t8555/

 

[gildersol]

You could check with a multimeter, which relay coil terminal shows +12v when the DME relay is energised. The small relays coils are pins 1 & 2

Or you could swap the small relays over to see if it helps.

Could be worth checking that the DME itself hasn't got wet as this can cause similar problems.

 

[bitmonkey]

You could check with a multimeter, which relay coil terminal shows +12v when the DME relay is energised. The small relays coils are pins 1 & 2

Or you could swap the small relays over to see if it helps.

Could be worth checking that the DME itself hasn't got wet as this can cause similar problems.

Thanks, I will do this and then if that doesn't tell me what's going on I guess I'll have to get the top of the fusebox off and go spaghetti diving.

Just my luck to have the only M3 in the world with this fusebox!!!!!!!! :hihi

thanks

 

[gildersol]

Thanks, I will do this and then if that doesn't tell me what's going on I guess I'll have to get the top of the fusebox off and go spaghetti diving.

If you do, the wire is red/white and goes from pin 87 on the DME relay to the coil of the fuel pump relay:thumbsup

 

[thegoodbadandugly]

I would provide the fuel pump fuse with 12v battery supply via a fuse, make one up yourself, or use a supply from a neighbouring fuse with a jumper wire.
If the car starts then you know that whoever removed your alarm has made a **** up, or there is some other wiring issue, but you know the fuel pump relay, dme relay, and the dme are all ok.
Find out where the fuel pump cut was made for the alarm, under the passengers carpet???????? and check the wiring.

 

[steve_2202]

hi i am sure i read somewhere that some m3's had 2 fuel pumps if u google it u should find it