Fuel Pump wiring HELP!
Fuel Pump wiring HELP!
I need help wiring up the fuel pump, iv done the 2.5 conversion the car fires up fine but obviously i done have fuel going in. I followed murrans thread to wiring the car up but when it come to wiring the pump im confused...."fuel pump is simply earthed and fed live via the violet/red, pin 13 (id suggest putting an in line fuse in this just as it comes out of the c101 connector". I cant seem to find any violet red wire and when i located the fuel pump i found that it had 3 brown wire connected to it. Urgent help needed please!
79' BMW E21 323 M20B25 lives!!!
- e-einundzwanzig
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Re: Fuel Pump wiring HELP!
I think you have to have pin 3, the green wire.
Martin
Martin
I took the corner at high speed, came in the ditch, drove straight through a garden, flipped over 4 times and then I lost control of my steering-wheel!
Re: Fuel Pump wiring HELP!
where do i find the green wire? on the pump there 3 brown wires.
79' BMW E21 323 M20B25 lives!!!
- e-einundzwanzig
- E21 Pro
- Posts: 889
- Joined: Fri Nov 14, 2008 1:02 pm
- My E21(s): '82 318i manual
- Location: Dinxperlo, the Netherlands
Re: Fuel Pump wiring HELP!
the green wire on the fusebox. you have to connect it to the relais, at least I did, I didn't have a feulpump when i began the conversion.
Martin
Martin
I took the corner at high speed, came in the ditch, drove straight through a garden, flipped over 4 times and then I lost control of my steering-wheel!
Re: Fuel Pump wiring HELP!
can you show me some pictures please. where am i ment to have a relay
the only relays i have in my fuse box is low beam relay high beam relay and relief relay
79' BMW E21 323 M20B25 lives!!!
- e-einundzwanzig
- E21 Pro
- Posts: 889
- Joined: Fri Nov 14, 2008 1:02 pm
- My E21(s): '82 318i manual
- Location: Dinxperlo, the Netherlands
Re: Fuel Pump wiring HELP!
e21rana wrote:can you show me some pictures please. where am i ment to have a relaythe only relays i have in my fuse box is low beam relay high beam relay and relief relay
you need 2 fuelpump relais. at least, i think...
Martin
I took the corner at high speed, came in the ditch, drove straight through a garden, flipped over 4 times and then I lost control of my steering-wheel!
Re: Fuel Pump wiring HELP!
the fuel pump relay is one of two that are clipped onto the side of the fuse box...the socket for the pump relay is part of the wireing loom for the engine which plugs into the fusebox ....edd...e21rana wrote:can you show me some pictures please. where am i ment to have a relaythe only relays i have in my fuse box is low beam relay high beam relay and relief relay
http://www.e21.ee/galerii/album/album216/aaa.sized.jpg
hope this pic helps with my explaination..
Last edited by mr edd on Fri Jul 30, 2010 8:44 pm, edited 2 times in total.
e21 320 (12/1975) 320i/4 (3/77)running gear.
e21 316 (1981) TRE702X.
e21 316 (1981) TRE702X.
Re: Fuel Pump wiring HELP!
ok so how do i feed a live and earth to the pump?
79' BMW E21 323 M20B25 lives!!!
Re: Fuel Pump wiring HELP!
the fuel pump is pretty basic.
you use the fuel pump output on the c101 and then you can basically follow the below diagram

you use the fuel pump output on the c101 and then you can basically follow the below diagram
[img]http://s13.photobucket.com/albums/a285/nasbucket/forumsig.jpg[/img]
Re: Fuel Pump wiring HELP!
right, the relay is on the motronic loom, one of the three together, but never mind about that.
the violet/red wire (on the car loom) green/violet (on the engine loom side), pin 13. are the colours and position of the live feed for the fuel pump at the big round multiplug code named the "c101" where the engine loom plugs into the car loom on an e30.

^^^^ c101 plug. pin 13 on this!
this live comes from the fuel pump relay and is switched in by the ecu on cranking
the three brown wires on the tank sender unit are for the fuel level sensor? what fuel pump are you using? 4 cyl e30 in tank pump or the e21 323i pump under the car?

^^^^^^ 4cyl e30 in tank pump.

^^^^^^ c101 plug mounted where the e21 tci unit was, and wires from e21 fuse box connected.
the violet/red wire (on the car loom) green/violet (on the engine loom side), pin 13. are the colours and position of the live feed for the fuel pump at the big round multiplug code named the "c101" where the engine loom plugs into the car loom on an e30.

^^^^ c101 plug. pin 13 on this!
this live comes from the fuel pump relay and is switched in by the ecu on cranking
the three brown wires on the tank sender unit are for the fuel level sensor? what fuel pump are you using? 4 cyl e30 in tank pump or the e21 323i pump under the car?

^^^^^^ 4cyl e30 in tank pump.

^^^^^^ c101 plug mounted where the e21 tci unit was, and wires from e21 fuse box connected.
Jeroen wrote:Bmwe21.net, for all your insurance solutions
Re: Fuel Pump wiring HELP!
im using the standard e21 323i pump (for now anyway iv been told to switch it an e30 one but thats a totaly different matter now) the problem is iv looked everywhere on my loom and i cant find this red/voilet wire ANYWHERE its doing my head in now. lol
79' BMW E21 323 M20B25 lives!!!
Re: Fuel Pump wiring HELP!
nas you dont need two relays, the 4 pin one on the motronic loom is already there.
just find the pin 13 wire as it comes out of the c101, put a fuse in, i ran the wire to the e21 fuse box and did this...

the e30 has a 7.5 amp fuse, but if your using an e21 323i pump you'll need like a 20 amp as it darws more current and will blow a 7.5 amp fuse no probs.
take this wire to the fuel pump live and simply earth the other side.
just find the pin 13 wire as it comes out of the c101, put a fuse in, i ran the wire to the e21 fuse box and did this...

the e30 has a 7.5 amp fuse, but if your using an e21 323i pump you'll need like a 20 amp as it darws more current and will blow a 7.5 amp fuse no probs.
take this wire to the fuel pump live and simply earth the other side.
Jeroen wrote:Bmwe21.net, for all your insurance solutions
Re: Fuel Pump wiring HELP!
the wire is red violet on the CAR LOOM SIDE of the c101 plug. its green violet on the ENGINE LOOM SIDE. but either way its pin 13 on this the c101 plug........e21rana wrote:im using the standard e21 323i pump (for now anyway iv been told to switch it an e30 one but thats a totaly different matter now) the problem is iv looked everywhere on my loom and i cant find this red/voilet wire ANYWHERE its doing my head in now. lol

Jeroen wrote:Bmwe21.net, for all your insurance solutions
Re: Fuel Pump wiring HELP!
the 323i fuel pump is under the car. id fitted the e30 pump but either will do the job just fine.
the three brown wires you speak of under the back seat are for the level sensor, not the pump.
have a look under the car for the 323i pump, find out what colour the live to the e21 pump is, then find this wire at the e21 fuse box/car loom..... connect this wire to the c101 pin 13 wire.
the three brown wires you speak of under the back seat are for the level sensor, not the pump.
have a look under the car for the 323i pump, find out what colour the live to the e21 pump is, then find this wire at the e21 fuse box/car loom..... connect this wire to the c101 pin 13 wire.
Jeroen wrote:Bmwe21.net, for all your insurance solutions
Re: Fuel Pump wiring HELP!
Ooooh I thought that was the fuel pump becuase on your thread you have connected wires to that. But that helps a lot thanks. Where about under the car would I find the pump? Driver side or passenger side?
79' BMW E21 323 M20B25 lives!!!