View Full Version : Trying to get M20 to start - no luck

10-27-2003, 08:34 AM
Hi all,
I'm putting an M20 engine in my 2002, but I can't get it to start. It seems like I've tried everything...

AFAIK I have all of the critical signals, but if somebody sees something I have missed, let me know. If I haven't listed it, assume I have done nothing with it. I am not much of a mechanic so it is easy for me to miss the simple things.
From the 6 into 2 page, here's the list of important signals. The bold ones are the ones I have connected to something.

325 Harness
2002 Harness

#1 Blue
Blue of Voltage Regulator

#4 Brown/Violet
Coolant Temperature

#5 Black/Brown
Oil Pressure

#6 Green
ECU Power

#7 Green
Coil Power
Same Green as above

#9 Black
2 Black Wires (18 Gauge)

#13 Violet/Red
Fuel Pump
Direct to Fuel Pump

#18 Black/Yellow
Starter Black (10 Gauge)

OK... the "15" terminal of the coil is hooked directly to the battery, and the '1' terminal of the coil is going to pin 13 of the diagnostic connector (according to a guy on roadfly Pin 13 should be the same as the ECU pin that grounds the coil). The fuel pump is hooked up manually and is pumping gas. When I turn the key, the engine turns over but I have NO spark and the fuel injectors do not fire (I hooked one up to an oscilloscope). I have a generic autozone relay instead of the main relay, and I do not have a fuel pump relay (because the fuel pump is being fed manually). I never hear the main relay click. I have tried swapping the speed & reference sensors but that had no effect. Can anyone think of anything that I am missing?

It's pretty clear at this point that it has to do with the ECU. I have no other ECU to test it with, so it could be bad... but is there anything else that I could be missing?


12-14-2003, 11:52 AM
I want to say MAF probaly wont help

Good luck

Jay Stock E30
12-15-2003, 09:22 AM
I have a friend who recently swaped a 325i motor into a 528e...there are several wires haning out near the ecu that are in the same bundle of cables as the ecu harness, but not run through the connector. One of those is key to getting the engine to start. I'll contact him and see if I can get his wireing diagrams if you think that wil help.

Keep us posted on your 2002 m20..I'd love to ride in one someday.

precision tuner
01-13-2004, 11:01 PM
check all of the electrical theres some that if backwards the car wont start. is there fuel or is the pump priming with the ignition key? is there spark? if not theres a sensor near the 20 pin connector it is for the ignition impuls sensor(the wire coming off the coil wire on spark plug wire set) and speed sensor the one to the left of the harmonic balancer. if the two wires are backwards where they meet at the 20 pin connector it it will shut off the fuel and spark.....happened to me.

01-14-2004, 06:51 PM
i guess hes gone, hasnt replied since he posted and that was over 3 months ago. too bad though, i would have liked to see how it ended up.

one day, i would like to have a 2002 project car and throw in an s14