318/323i Loom Differences

[e21Keith]

Rebuilding my 323i but the main loom I have is from a 318i carb. What differences are there between the two?

The headlight loom is different, 2 headlights against 4
There is a feed to the fuel pump
Engine loom will be different
Additional lamp inside the bootlid to illuminate the boot

Are there any other differences i need to be aware of?

[Jeroen]

Well the wiring to hood and bootlid lighting are separate looms that hook up to any of the looms, that shouldn't be different, but I can think of a few more significant differences between a carb model (not being 318i ) with TN starter or choke compared to the 323i with wiring for the thermal time switch, warm up regulator and aux air valve to name but a few. Think I'd try to source a 318i or 323i loom but hey, I'm lazy

[e21Keith]

I have a 323i engine loom so I'm hoping all the bits on the engine should be covered.

[mr edd]

Wiring for boot light plugs into main loom in the boot close to the passenger side boot hinge.wires for electric fuel pump connect to main loom under front corner of rear seat on passenger side.fuse box is slightly different as the relay on the single headlight fuse box has five pins and cuts the dip when the highbeam is switched on...not a big issue ....main loom seems to be universal to all models..... i built a 320 into a 316 shell and all the secondary looms and fuse box from the 320 plugged into the 316 main loom fine...edd..

[e21Keith]

I've seen those cables at the front left of the rear seat on the 323i I had to break and they weren't connected to anything, the fuel pump cables were much thicker. Love to know what that was for though!

[mr edd]

The pump plus wire is the thick green wire with a black stripe and brown is neg wire