318iS - What are these?

[E30-Andy]

Couple of things I was wondering about while doing my iS engine conversion:

Can anyone tell me what the 3rd relay is used for, it was missing on my iS wiring loom and I wondered if I will need it.

Also I have one plug remaining on the engine loom - anyone know what it's used for.

[Andy325i]

I had this plug floating in the breaze on my M40 318i 1990. Not sure what is was for lol

[6potWil6pot]

Yes thats in the engine bay of even my car, not sure why it exists...

[irishstevo]

Apparently , the missing relay is for the vacuum advance . Not sure what that is but on my m42 it's not used . Likewise for the plug/connector , it's just floating around in space .

[Brianmoooore]

Don't know the iS layout, but the spare relay socket next to the main DME relay and the fuel pump relay on proper E30s with 6 pots, is for the heater for a lambda sensor fitted on cars with a cat.

[irishstevo]

That's correct but on the 4 pots , the relay layout at this location is differant

[Karan]

Couple of things I was wondering about while doing my iS engine conversion:

Can anyone tell me what the 3rd relay is used for, it was missing on my iS wiring loom and I wondered if I will need it.

Also I have one plug remaining on the engine loom - anyone know what it's used for.

u dont need those 2......

is it in a and running then?

[Demlotcrew]

Couple of things I was wondering about while doing my iS engine conversion:

Can anyone tell me what the 3rd relay is used for, it was missing on my iS wiring loom and I wondered if I will need it.

Also I have one plug remaining on the engine loom - anyone know what it's used for.

This relay is for Cat equiped cars, the plug is for a valve for the petrol evaporator tank you removed, again its only used for cars with a cat.

Andrew

[E30-Andy]

That makes sence now.

Cheers

[Demlotcrew]

Now, let this engine warm up to half way before you take it past 3k rpm, or it will not last long.

Andrew