Does anyone have the exact instructions and/or diagram on how to wire up a harness from a m20b25 engine to an eta car? I've got the "I" engine in and just need help wiring it up.
Thanks in advance.
Wiring harness instructions
Moderator: martauto
thanks! I know the eta has two rows of pins at the ecu and the 'I' has 3. do the extra wires just stay unconnected?
If i encounter the live to earth situation, do I just cut the wire so they don't connect, or do I have to reroute a new earth too?
If i encounter the live to earth situation, do I just cut the wire so they don't connect, or do I have to reroute a new earth too?
- Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
Does the fuel pump run when the engine is cranked? You can push a wire from a small 12 volt bulb into fuse 11, with the side of the bulb connected to good body earth (rear bonnet bracket) to check.
- Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
Won't be the CPS if the fuel pump runs. Pump relay is activated by integrating pulses from the CPS.
Have you confirmed that there is 12 volts on the + terminal of the coil when the ignition is on, and that it is still there, if a little reduced, when the engine is cranking.
Have you confirmed that there is 12 volts on the + terminal of the coil when the ignition is on, and that it is still there, if a little reduced, when the engine is cranking.
- Brianmoooore
- E30 Zone Team Member

- Posts: 49358
- Joined: Mon Jan 10, 2005 11:00 pm
What's the solenoid got to do with anything????
Do I have this correct:
You have a 325e with a 20 pin round C101 engine loom socket, and have fitted a M20B25 engine, complete with its ECU and loom, with 20 pin C101 plug?
The engine will crank, but you do not have sparks from the king terminal of the ignition coil when doing so, although there is 12 volts on the + terminal of the coil?
The fuel pump definitely runs when you crank the engine?
Do I have this correct:
You have a 325e with a 20 pin round C101 engine loom socket, and have fitted a M20B25 engine, complete with its ECU and loom, with 20 pin C101 plug?
The engine will crank, but you do not have sparks from the king terminal of the ignition coil when doing so, although there is 12 volts on the + terminal of the coil?
The fuel pump definitely runs when you crank the engine?
took it to a bmw mechanic. he basically told me that the idiot that put it together (another mechanic) put all the E sensors on with the engine, which is why it does not start.
I put on the following: I crank pulley, I CPS sensor, I throttle body, I oil level sensor, I harness (installed properly), I vacuum lines, I oxygen sensor and so on.
It turned over on the first try but I quickly turned it off so I can finish the cooling system. (for which i have already started a new thread)
Thanks for the help guys.
I put on the following: I crank pulley, I CPS sensor, I throttle body, I oil level sensor, I harness (installed properly), I vacuum lines, I oxygen sensor and so on.
It turned over on the first try but I quickly turned it off so I can finish the cooling system. (for which i have already started a new thread)
Thanks for the help guys.

