320 ECU on 325?

[bimmaman]

Hey people,

I have recently had a new engine fitted in my 316, but what is weird is that although it is a 2.5 (M20), it has the ECU from a 320... The car we took the engine from was originally a 320, and the previous owner had obviously fitted this engine.

I have had no problems with the engine whatsoever, so is having the wrong ECU serious? Would this be the cause of my electric windows/sunroof only working when I open the door??

Weird or what!?

[blingsta]

your windows would only work when the door is open anyway (without ignition)

[cass1_5503]

i had a similar problem with my old 316i with the windows if its with the ignition on and they still dont work check 1 of the relays behind the glovebox i think it is 1 of these that controls the windows well it worked on my car anyway hope this helps

[Brianmoooore]

The only difference between a 320 and 325 ECU is the chip. If this has been changed for a 325 one, or a performance 325 chip then it will be fine. Otherwise, the engine will not be running properly.
Window problem will either be fuse 17 blown, or, if the mirrors don't work either, a problem with the wire that goes to the smallest terminal on the starter motor.

[bimmaman]

Cheers guys...

I've checked fuse 17, and its fine... checked the wires on the starter motor, pulled them off, and put them back on again... Sat in my car, turned the ignition on, with doors closed, and the windows worked!!!
Started the engine, and they don't work again
Switched off, pulled wires, plugged em on again, and the windows work again, right up till I start the engine, then it goes back to only working when the doors are open...

Whats going on??

[bimmaman]

Sorry to be a PITA, but can anyone help?

[Quaser]

which colour wire is it? is it theone at the top or the bottom?

maybe you have a break in the wire which is ok until the engine starts shaking

i think its the yellow wire - i have run a new one to behind the glovebox on my car and all works ok now!

i had the same problem on my cab!!

Q

[bimmaman]

hmm. I took both those spade connectors off, and put them back on again. Which wire is the yellow one? I am colour blind!!!

[Brianmoooore]

On all the E30s I've worked on the starter control wire has been black/yellow, and the unloader relay wire has been green/black. Also, the connections have been by ring terminals, not spade connectors.

[bimmaman]

So is this simply an earth problem? If so, which of the above terminals should I connect to earth? Or are my relays faulty?
One other thing, my offside rear indicator bulb seems to keep blowing... is this connected someway?

[Brianmoooore]

Niether of the terminals connect to earth. The starter motor earth connection is through its mounting bolts.
The starter motor terminal to which the black/green connects is effectively an earth terminal, except when the starter is operating, when it becomes 12V+.

[bimmaman]

i think its the yellow wire - i have run a new one to behind the glovebox on my car and all works ok now!

Ok, please excuse my ignorance... So I should connect a wire, where?

What do I need to do to fix this annoyance?

[Brianmoooore]

Got to find out why your starter motor is different from ones I've seen first, and identify the colours of those wires.