e30 M60B40 Wiring Help? 404 ECU/DME converted from 484

[GB / John]

Just doing the conversion on my e30, engine is in, and wired up, but wont start, it just turns over without trying to fire.

When I had the engine in an e34, it had a 484 ECU/DME, this was swapped for a 404 ECU/DME. I had to cut wire to pin 66 on ECU/DME, and bridge pins 1 & 3 on EWS box under dash. It worked fine when in the 540. I only swapped the engine, and main engine harness, leaving the EWS parts on the 540 as I assume using a 404 ECU I dont need any of the EWS wiring.

This is how I have wired it:-



Anyone see if I have done anything wrong?

[JGood]

Just doing the conversion on my e30, engine is in, and wired up, but wont start, it just turns over without trying to fire.

When I had the engine in an e34, it had a 484 ECU/DME, this was swapped for a 404 ECU/DME. I had to cut wire to pin 66 on ECU/DME, and bridge pins 1 & 3 on EWS box under dash. It worked fine when in the 540. I only swapped the engine, and main engine harness, leaving the EWS parts on the 540 as I assume using a 404 ECU I dont need any of the EWS wiring.

This is how I have wired it:-

Anyone see if I have done anything wrong?

Have you verified that EWS is indeed causing the issue? Are you getting spark or fuel? I know you pulled a running engine and it should work perfectly just as it did before... But after my ridiculous one year battle with my engine, I no longer assume anything.

Sorry, I can't help with the EWS related stuff, I've never messed with it.

[GB / John]

Not checked for spark yet, will be checking for that next time. Fuel is flowing back to tank, but not checked if injectors are injecting yet. Does the wiring above, look about right? Was mainly wondering with it being a ECU swap, maybe I need to bridge other wires as there is a Green 3mm wire in Pin 7 e34 harness that I havent connected?

[GB / John]

ok problem semi solved.

It sounded like it was just running on the starter motor, not trying to fire at all. So I checked for lives to the ECU, the Ignition Live to ECU from Pin 7 e30 side was not going live, so ECU is not getting power. Pin 6 was getting an Ignition Live, so I bridged Pins 6 & 7 to power the ECU and the engine started immediately.

Is bridging Pins 6 & 7 ok for a permanent fix, or should I wire an Ignition Live to Pin 7? Whats the difference between Pin 6 & 7 e30 side?

[Jean]

ok problem semi solved.

It sounded like it was just running on the starter motor, not trying to fire at all. So I checked for lives to the ECU, the Ignition Live to ECU from Pin 7 e30 side was not going live, so ECU is not getting power. Pin 6 was getting an Ignition Live, so I bridged Pins 6 & 7 to power the ECU and the engine started immediately.

Is bridging Pins 6 & 7 ok for a permanent fix, or should I wire an Ignition Live to Pin 7? Whats the difference between Pin 6 & 7 e30 side?

Hate to bump this , but what was the actual problem here?

I am asking because I am going to be using a 95 540i manual harness and have a 404 DME on hand. My understanding is EWS is all in DME, and harness should work fine....

484 DME is the EWS, 404 does not have any EWS.