Replacing 7mgte ecu

[kemicalx]

G'day guys,

I've began preperation for the installation of my EMS, it came with a complete loom and an EMS 3 coil ignitor,

I unwrapped the standard loom today and did some labeling/wire tracing. It all looked like it should be pretty straight forward.

My question though is, Because i have another loom for the EMS which has plugs/sensors for everything it needs to run. Can i disconnect/cut the things I've highlighted red from the standard ECU and just leave things like the knock sens., temp sens., speedo, etc connected while things like TPS and Cam Pos. can just be unplugged from the standard loom and then plugged into the new one?

Or, Am i better off unplugging the original ECU intirely, seems like the easier option, but i don't want to do that then have a bunch of stuff in the car stop working.

 

[Halsupramk3]

It would be good to know what brand ems you will be upgrading too.

It is usually better to use a matching plug that will plug directly into the ecu so you dont have to solder. crimping can also change the resistance reading of a wire and some of these sensors are resistance output.

I would need a little more information about what it is you are trying to do and info about what you are using to tune.

 

[kemicalx]

It's an EMS DualSport, It's a few years old and made in australia so i doubt you guys will have much info on them. It has it's own wiring loom suited to a 7mgte.

What i originally wanted to do was have the EMS controlling the engine, while the standard ecu still did the things the EMS can't (like knock sensing) However I was having a chat with one of the blokes from Toymods.net and it sounds like it is just going to be easier to remove the stock computer intirely.

I've got a wideband o2 sensor for some home tuning as the EMS has lambda readout, Home tuning will do until i can get the new downpipe and exhaust installed, then i'll take it to an EMS dealer for a propper tune

 

[kemicalx]

A couple more Q's,

For an engine to start correctly is this how things should be switched via the ignition switch?

- On AM2 the fuel pump is connected to power, as are the coils, while the injectors are already connected to 12v, but will be switched on/off via ground by the EMS once the engine is actually rotating.
- On AM1 the starter motor and CSI kick the whole lot off,
- Once started the car stays on AM2 but now with the engine running.

Also would any of you have an idea as to what pin 27 (Pump relay control) of the EMS does? I first presumed it switched the fuel pump on, however there is no output from pin 27 when the EMS is on, Also there is no output from the relay that goes to a fuel pump

Is it likely it just goes in place of the standard ECUs FPR output that switches the fuel pump to the resisting circuit? (Is this used for a hard rev limit or something?)

Finally, will it be ok to do away with the EFI Main Relay and the Circuit Opening Relay?

I’ve been messing with some wiring diagrams in paint and *think* I’ve wired up everything correctly, but I’d appreciate it if someone could have a look over it all and see if you think she’ll work. Cheers guys,

My butchered diagram (sorry if it's a bit messy)


And just for reference a few standard wiring diagrams

Fuel system


Circuit opening relay


EFI main relay


Starter motor


Cheers all, any info on this stuff would be a great help