I have a '92 CPFI 4.3 swap. And I did the wiring for a friend's '93 CPFI 4.3 into a CJ5. Mine has the 4L60 trans behind it, his had a manual transmission (and almost no working gauges....someday he'll re-do the dash).
I have wired in a USB cable into mine, and installed TunerPro RT onto my lap top so I can read and log parameters and look for/diagnose issues.
I've done wiring for literally dozens of engine swaps. Mostly subaru engines, but a few other things. The CPFI was one of the easiest, very nicely laid out, unplug the harness from the body, and you really don't have much extra. I got an OEM wiring diagram book on ebay for the '92 Blazer, and found some decent wiring diagrams in my Haynes manual for the toyota (this left some to be desired since mine is a turbo with an automatic and digital gauges, but you probably won't have this issue). The GM book was completely accurate for what we needed for the '93 swap into the Jeep (there were some extra wires in the harness for the transmission, but everything we needed was covered).
My 22RTE and the 4.3 both use 2 temp sensors. One for the engine, and one for the gauge. The gauge sensors are interchangeable. I put the 22RTE one in the 4.3 block (passenger side, between exhaust ports).
*technically* the GM oil pressure sensor is not for the ECU. It gives power directly to the fuel pump. The ECU does NOT supply power to the fuel pump, but it does read it. The ECU turns on the fuel pump relay to prime the system, but when the engine is running, it is oil pressure that powers the pump while the engine is running. The oil pressure sensor is both a on/off switch, that powers the fuel pump as I mentioned, and it has one wire that supplies calibrated resistance to ground for the gauge. As far as I could tell, the resistance was considerably different than what Toyota uses. Luckily, both companies use standard pipe thread for their sensors. So some hardware from the plumbing section at Menards left this:
Now, I had the fuel pump relay begin to fail on the trial (I had other issues too, ended up being the optical sensor in the disty), when I plugged my laptop in, I was only getting 9v for the fuel pump when priming, and then it jumped to battery voltage once oil pressure came up. I wired the pump to one of my un-used auxiliary light circuits that I added with the swap. I have left it this way for now....may or may not wire it back.
Tach. I have a signal converter to convert the 6-cyl signal to 4-cyl. I have used this on Subaru analog gauges before, doesn't work with my digital tach. So I have an aftermarket tach...It's possible a 6-cyl OEM tach would read correctly directly from the signal wire on the 4.3 coil.
I have the blazer fuel pump mounted to the toyota bracket in my tank. Took a few minutes with the dremel to modify it to accept the GM strainer....but it worked fine.
James92toy is dead on, "Take your Toyota engine harness off . Unplug it from body harness at passenger side kick panel . Cut the engine harness about 6 " from plug . This is where you will be wiring tach , oil ,temp , ecu power to and then plug it back into body harness. Kinda scared me at first , once I figured it out it was easy."
I pulled it all in-tact, and found the wires I would need (having the plugs at the engine made it easier to identify the correct wire) before cutting back the un-needed. Then spliced into the GM harness where needed. So it is plug-and-play just like stock.
I had to do some wiring diagram-studying, and note-taking to track down all the power wires. There are a couple switched and un-switched, but everything else was pretty simple.
I simply hooked up the VSS sensor from my toyota speedometer to the GM ECU. When I hooked up my laptop, I found out that the ECU thinks I'm going twice as fast as the gauge does, as far as I can tell, the overdrive operation is the only thing effected. Jagsthatrun.com offers a speed sensor that can be attached in-line with the toyota cable at the tcase, I will probably use one of these.
My friend's Jeep, we just omitted all transmission-related wiring. No VSS, etc. It seems to run fine (it's not street driven, so it might not be perfect, but it gets around). It does not have a CEL hooked up either, so I'm sure it's tripping codes...
Pics:
CJ5
Mine:
Posted by: irwinirwinlinburger0253237.blogspot.com
Source: https://www.yotatech.com/forums/f163/4-3-wiring-what-all-required-276631/
