Standalone ECU Attn Megasquirters who used the MS harness

[Matt300ZXT]

So I'm curious what you guys did who ran Megasquirt and it's own harness and chucked the stock ECU and harness about a few items on the 1UZ. What did you guys do about the starter, or is that harness wired separately from the fuel injection harness? I was also curious about the knock sensors but I guess those can wire into the Megasquirt harness. Also, what about things like the coolant sensor for the gauge on the dash, and the oil pressure gauge in the dash? The spare 1UZ I bought I'm doing this to had the harness hacked to bits to just pull it out of the car, so I'm not 100% on what is actually wired into it and what may be part of the chassis harness or a subharness.

I'm just curious what issues I might have to address from running a Megasquirt and it's own harness for the injectors and various sensors it needs to function.

 

[devojet]

Not much you need to watch out for.

There are 3 coolant sensors. one for the ecu (wire to MS), one for the dash gauge and the third is a switch that controls the cold start injector. You will want to disconnect the cold start injector as it is not required with MS.

You will also need to add an air temp sensor.

I didn't use the knock sensors on my install.

Just run a wire from the oil pressure switch to the dash light.

Starter just has two wires. the main battery wire and a thick black wire that runs in the engine loom is for the start solenoid.

The only other thing is the alernator but that should have a seperate wiring loom. Have a look in the technical documents on this web page as there are diagrams that show how the charging system is wired.

Cheers

Daniel.

 

[18crxt]

i just stripped the wires out of my factory harness and repined them to a honda plug so i could disconnect them if needed and the other side to the ms harness and bang... if you can trace wires and make a diagram you can do a ms..

 

[watty]

@Matt300ZXT

Wiring up the 1uz isn't that hard. Just take it sensor by sensor. I've got one in my 240sx running on an MS-I v3. I can't speak for the sc400, but if it is like mine, there are a few wires that run through the engine harness just to get through the firewall. I figured that out when I realized I didn't have windshield wipers. lol The biggest thing you will need is the FSM for the sc400. From there, just start staring at the wiring diagrams until they make sense and then start tearing into the wiring harness before you forget everything.

I'm in Huntsville, AL just down the road. If you are ever going to be in the area and want to take a look at my setup, I would be more than happy to show you and give some pointers.

Also, fyi, the guy who runs GlensGarage.com for MS stuff lives about 10 miles from me. So, if you need parts quick, he can get them to you in about a day.

s14asilvia #at# gmail.com

Watty

 

[bartledoo]

@Matt300ZXT]
just start staring at the wiring diagrams until they make sense

Haha that's exactly what I tell people when they say they don't understand wiring diagrams!