• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

Lh 2.4 conversion down to last wires


Feb 27, 2005
down to the last few wires on my LH 2.4 conversion on a 1984 240 Turbo. This car had been already converted to 2.2.
I got my lh harness & some components from a 1992 240, it has an 11 pin connector. Just got help from dbarton & sbabbs on a couple of harness questions but still have more.
First is where to connect the thick yellow/red wire. in the 92 240 fuse panel diagram it shows this wire to go to the input side of fuse 4, the output side shows to y/r to O2 sensor & in tank pump.The y/r thick wire comes from the fuel pump relay, I believe. The 1984 shows this wiring to fuse 5. Make sense to connect this thick y/r the same way? Some threads show this wire to a switched fuse? Someone has put a single in tank pump in this car, that wire comes from the same y/r output wire. Don't see the main pump wire doing anything.
Can the blue wire that needs to be switched go to an appropriate fuse, or is there an advantage to put it to 15 on the ignition switch, whitch looks like a PITA to do?
Long way to ask simple questions which probably have easy answers, just want to get it right.
Thanks, Paul
It needs to be a switched fuse for sure. Like you said it powers the fuel pump. So you can't have the fuel pump going all the time.

It also needs to be a certain amp fuse to run the pump. It needs to kick on the power when you turn your ignition on, and needs to stay powered while your cranking to start. With lh2.4 you turn the key on, then you hear the fuel pump prime for 5 seconds. That is how it works, then as soon as you crank the starter it will kick the pump back on as it knows your trying to start the car then from the crank sensor.

Now the blue to starter solenoid wire is super easy. Your over thinking it. IT has to connect to the wire that triggers the starter relay at the starter. What I did is trace that wire to where it comes into the car and under the dash to the key switch and just tied it in under the dash, you know, connected it to that same wire. I used one of those plastic connect a wire to another wire but leave the other wire still connected connectors. The blue wire is the wire that tells the ECU that you are cranking the starter and trying to start the car so it has to be connected at that wire...
You can take the blue (power with key on and cranking) and put it on the fuse block. I just used a volt meter to find a fuse that was hot with key on and while starting.
Easy peasy.
Isn't the blue only supposed to be hot with power while cranking only? That is how I hooked it up, and it works for me, but do what you want.

It tells the ECU your trying to start the car.

Maybe he don't have bolt meter or know how to use one, best to just attach it to the correct wire, that wire that starts the car....

My fuel pump is wired directly to the ignition circuit and only runs when the ignition is on (doesn't prime for 5 seconds)

Therefore, when I crank, the pumps turn off. Although I've never had an issue with starting, fuel pressure, or anything. Works like a charm, you just gotta let it run for a second when you turn the key.
We'll regardless the way it works is it runs for 5 seconds when you first give it power, then it will run when it gets crank signal if it has power.

I'm sure there are a lot of ways to make it run. Ever taken out the relay and jumped it instead with wires?