Help with 3.4 wiring

[mansep2]

I am going to transplant a 3.4 1995 fiebird engine and gearbox into my 1973 MGB convertable and so far I have got the engine and gearbox complete with all of the engine wiring harness and ECM.

What I need to know is I can see the wires that travel into the car with 4 connectors but not sure which wires are which, so I am looking for maybe a wiring diagram that shows those connections or someone who can list them down for me. That way I can correctly connect them up with my cars wiring.

Any help would be great.

Thanks Paul

[deathamatend]

I assume you mean the connectors for the engine computer/ECM. if you didn't get the ECM with your drivetrain I would go back and try to get the one that went with it exactly otherwise it is going to be a big problem. I hope the wires are not cut otherwise you will need to solder and shrink tube them or you will have phantoms galore. Everything is a sensor/engine control harness wire. All you need is battey voltage to supply constant power and a switched power source from ignition switch. All the other wires go from engine to ECM. Is the setup OBD II? You would need to know what application it is to service any sensor/issues that crop up. In one sense You cannot plug a connector where it doesn't belong. They are keyed and color matched. I would only do what you are trying as a transplant-that is you have the entire doner car there with you as you are going to GM a MGB. I have worked on many MG/MGB/Midgits and am no fan of engine controls on any of them, so good luck, keep us posted, and post pictures. We are here to help and don't hesitate to ask anything.

[mansep2]

No I dont have the car so cant cross reference but I do have the ECM and all is connected so it is only what connections to make to marry into the MG system.
Such as which is the ignition feed wire, starter feed wire, tach wire etc.

[23TrackroadsterV6]

Shop ebay for a 1995 Firebird service manual. Get the OEM GM manual as it has very detailed wiring diagrams. I bought one for an S-10, one for a Camaro's and one for a Trooper so I can integrate the Isuzu 3.1 TBI with the Camaro ECM. Lots of the same wiring colors used for the same sensors in both GM vehicles

[pbsch]

Hi Paul,
I mailed you the diagrams someone on this site shared with me. I am using a hybrid 1994 Camaro harness and a 7227 ECU from a Lumina. What I did with mine was found the big relay that powers the ignition system on the OEM engine and used it as a switched power supply for a small fuse block with four terminals (I actually replaced that large solenoid style relay with a much smaller solid state one from the Camaro - it's rated at 40 amps and should never see more than 5 or 6 if I had to guess from the gage or the wires. There are two pink wires that come from the injector harness that I ran through one of the fuses, there is a single pink wire from the coil pack and a single pink wire from the ECU. The fourth I assigned to the alternator. I have a voltmeter in the dash, so I don't really care if the dummy light works or not. I fused each of these separately as that is how they were done in the original car (see the diagrams I mailed you). There is also an orange wire that runs off the ECU that needs constant power.