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86 325E M30B35 swap

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    86 325E M30B35 swap

    So my brother is swapping a b35 from a 94 e34 into his 86 e30 eta and is in way over his head with wiring.
    I am trying to help him, but im having one helluva time finding correct pinouts for anything.

    I have a 79 MB 300sd with a manual injector pump and of course no spark plugs because diesel (yay simplicity)
    Swapped in a 4 speed manual and put a bigger turbo on it that I rebuilt myself, so I can turn a wrench, as can my brother.
    I used to be a computer/cell phone repair technician and I build drones for fun, so im no slouch with electrical work either.

    Both cars were/are manual transmissions. The neutral safety switch was bypassed on the e30, so at least I dont have to worry about that lol.
    We have both sides (male and female) of the round x20/c101 (I believe that is the correct name) and whole harness from the e34 b35,
    and we have the chassis/female side of the e30 eta round x20/c101 that we're trying to adapt it to. Have the dme from the e34 as well.
    Motors in the car, just need to get a driveshaft connected and get the wiring sorted out and it'll be good to go.

    I have searched high and low for the correct pinouts and I cant find anything that matches whats actually in the car unfortunately.
    I have tried doing a continuity check from the e30 chassis side c101 to the fuse box, but I was only able to get a few hits and the readings I got
    were suspect and made me skeptical.

    I have mapped out the e30 chassis side plug as follows

    pin 1: blue
    pin 2: blue/yellow
    pin 3: unused
    pin 4: brown/purple
    pin 5: brown/black
    pin 6: green/yellow (heavier guage wire)
    pin 7: green
    pin 8: unused
    pin 9: unused
    pin 10: violet/red
    pin 11: white/blue
    pin 12: unused
    pin 13: violet/red
    pin 14: unused
    pin 15: unused
    pin 16: white/black
    pin 17: empty
    pin 18: black/yellow (heavier guage wire)
    pin 19: unused
    pin 20: unused

    I'm dumb, and left the b35 side plug at the storage unit with the car and didnt map it out yet, I can do that tomorrow.

    If there's anyone out there that can help with this, I'd dance a jig and be super appreciative. My brother even moreso than myself.

    Contrarily, I'm not afraid to set up new relays with toggle switches for the fuel pump, main relay and ignition relay. Starter confirmed to function correctly.
    As far as I understand it, the dme only really needs power, afm, o2, the crank position and control over the idle control valve? Or am I completely off base there?
    I know the spark is distributed mechanically, so its just a matter timing spark and controlling the injectors and idle?

    If there's anyone that can point me in the right direction for pinouts or adapting this damn thing to manually operated
    relays, I would seriously be grateful. I can provide any additional information if it helps the process.
    Attached Files

    It sounds to me like you are pretty frustrated trying to adapt the E34 harness to the E30. I know this because I've been in your (or your brother's shoes). Unless you're dead set on using the E34 harness, I'd recommend finding an M20b25 harness from a 325i. It is 95% plug and play with the remaining 5% being extending a few plugs (3 or 4 IFRC).

    But if the 325i harness isn't an option here are the 86 325e pin outs I wrote down from my endeavor. NOTE: Our colors do vary a little bit so there may be some discrepancy. I never completely figured out the E34 harness pin outs, but I can do some digging as I still have the harness.

    Pin 1: Blue - Alternator
    Pin 2: Blue/Purple - Oil Level Static
    Pin 3: N/A
    Pin 4: Brown/Purple - Coolant Temp Sensor
    Pin 5: Brown/Green - Oil Pressure Switch
    Pin 6: Green/Yellow - Fuse 9 and 27
    Pin 7: Green - Start Input
    Pin 8: N/A
    Pin 9: N/A
    Pin 10: Blue/White - Oil Level Dynamic
    Pin 11: White/Blue - Diagnostic Connector Pin 7
    Pin 12: N/A
    Pin 13: Green/Purple - Fuel Pump Relay
    Pin 14: N/A
    Pin 15: N/A
    Pin 16: N/A
    Pin 17: N/A
    Pin 18: Black/Yellow - Starter
    Pin 19: N/A
    Pin 20: N/A
    1986 325e Pearl White on Grey Houndstooth 24x,xxx miles M30b35 Swapped
    2002 525i Jet Black on Sand Beige 13x,xxx miles
    "This 2.5 liter inline six cylinder is smoother than my silk Versace underwear." -Vehicle Virgins