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LH2.4 Install/Conversion. Just 4 wires to make it run

Main questions now are:

Do I need to give the blue/yellow starter wire cranking 12v at the 9 pin connector if I already have cranking 12v at the starter solenoid via the engine bay connector?
-I don't think it's needed.

Why don't I have a blue/black speed signal wire?
- It could be a different color. Just trace it from the correct pin on the ECU connector.

The red/black wire, when given switched 12v, primes the fuel relay. Do I also need switched 12v for the blue wire?
-The blue wire needs to have power when the key is on and while cranking.

See above.
 
I'm glad this thread is still alive. If anybody has questions you can PM me and I wl do my best to help.


Peace!
 
Figured I'd share my experience getting 2.4 going on my 140 (which obviously had no ECU/fuel pump wiring before this swap). The cool thing is that my 140 ignition switch has the same pinout as the 2.4 switch, it seems.

Turns out I was using am '89 harness with a 9-pin connector by the computers. The blue wire that everyone talks about to power the system relay is actually red/black on an 89 harness. (still pin 35 on the ECU). This gets plugged into pin 15 on the ignition switch for switched/cranking power.

I ran the thicker red/yellow wire from that connector to an empty spot on my 140 fuse block. I wired my fuel pump to the other side of this fuse. I also connected the thinner red/yellow wire to the other side of this fuse for the O2 heater. This mimics the stock set up, based on the diagrams. Now the system relay primes the fuel pumps and O2, then powers them when cranking/running.

The blue/yellow wire from the 9-pin connector gets input that the starter is moving. The wiring to actually activate the starter is done through the gray connector on the engine side of the firewall. I connected the 9-pin blue/yellow to pin 50 of the ignition switch (power while cranking).

At this point, I don't have an intake manifold on the car, but i have checked all the LH systems. I have spark, fuel coming out of the line when priming and cranking, and doing the Function 1 test on pins 2 and 6 of the diagnostic unit shows me 1-1-1 codes, indicating that all is in order.

Thanks for the help, everybody.
 
I have a question regarding this conversion, how does the sensor wheel mount with a manual trans?

The crank position sensor? It reads the 60-2 pattern that is machined into the edge of an LH2.4 flywheel. Or, a few vendors offer lighter LH2.2 flat flywheels with the pattern machined into them.
 
Figured I'd share my experience getting 2.4 going on my 140 (which obviously had no ECU/fuel pump wiring before this swap). The cool thing is that my 140 ignition switch has the same pinout as the 2.4 switch, it seems.

Turns out I was using am '89 harness with a 9-pin connector by the computers. The blue wire that everyone talks about to power the system relay is actually red/black on an 89 harness. (still pin 35 on the ECU). This gets plugged into pin 15 on the ignition switch for switched/cranking power.

I ran the thicker red/yellow wire from that connector to an empty spot on my 140 fuse block. I wired my fuel pump to the other side of this fuse. I also connected the thinner red/yellow wire to the other side of this fuse for the O2 heater. This mimics the stock set up, based on the diagrams. Now the system relay primes the fuel pumps and O2, then powers them when cranking/running.

The blue/yellow wire from the 9-pin connector gets input that the starter is moving. The wiring to actually activate the starter is done through the gray connector on the engine side of the firewall. I connected the 9-pin blue/yellow to pin 50 of the ignition switch (power while cranking).

At this point, I don't have an intake manifold on the car, but i have checked all the LH systems. I have spark, fuel coming out of the line when priming and cranking, and doing the Function 1 test on pins 2 and 6 of the diagnostic unit shows me 1-1-1 codes, indicating that all is in order.

Thanks for the help, everybody.

Mine is up and running now, and for what it's worth, your description above is essentially what we did on my '81 242 (originally a non-turbo DL with K-Jet). Thick red/yellow now runs to the non-fused side of Fuse 5, for the in-tank fuel pump. My harness has the black/red wire so is an early LH2.4 harness too apparently. The yellow/blue wire for cranking signal is tapped into the park switch circuit that isn't used on manual cars, but is an artifact of the auto option, and seems to be in every wiring harness.
 
You can get around the Photobucket issue. The best is to install a Chrome plugin called "photobucket embed fix", but if you don't want to or can't run Chrome, just right-click on the photo and click "open image in new tab" (or similar).
 
This probably won't mean anything to anyone but I've got two wires going to my 940 ecu connector that I can't identify. (because the loom is no longer a part of the car) One pink and one white/green. The greenbook diagram doesn't show either colours as far as I can see. Any ideas?
Edit; Realised I can probably narrow it down by noting which pins are accounted for by all the other wires.
 
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The pinout numbering is what has been confusing me.

I was reading the connector pinout on the page below incorrectly. If you are looking directly at the connector (not the ECU) then you need to reverse that numbering convention. That took me way too long to figure out :roll:
http://ipdown.net/jetronic.info/tiki-index.php?page=LH2.4+Pinouts+and+Diagrams

I think I can make sense of it now. Those two wires I was confused about are not needed in my application - one is for auto trans and one for DLC connector.
 
EZK pin 5 is written up as being for "Supply voltage 30+. Power supply for on-board diagnostic (OBD) system memory and the adaptive function".

What adaptive function is this referring to? I suspect it's not required but I want to make sure.
 
EZK pin 5 should go to unswitched +12v. If you're using a LH2.4 harness, it will be connected to the 2 big red wires, and to the system relay, and to ECU pin 4. This is the voltage that keeps the learned/adapted behavior when the ignition switch is turned off. In the ECU, this includes fuel trim adjustment and saved CEL codes. For the EZK, it might just be saved CEL codes -- off hand, I can't think of anything else the EZK would save.
 
Yeah it's for persisting codes from the EZK. Not connecting it is just asking to make your life difficult when you're troubleshooting running conditions.
 
Hi, I have a 245 B21 carb euro car from 78 and have just acquired got all the parts I thought I needed for the swap. My car has a mechanical fuel pump and no computers just like Tfrasca. I was wondering how you implement the knock sensor on one of these older cars.
 
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