Gen 4 engine harness help

Bought an ls3 harness/e67 secondhand from a hotrod and trying to use it on a 67 c10 project. 09 6.0 with ls3 intake/accessories/TB, all of it should map right on. The MAP plug on the harness looks the same as the cam sensor plug and doesn’t go to the MAP. Correct location, wrong plug.


Front of drivers there isn’t a temp sensor wire or plug, same for alternator, but there is this funny 2 wire that doesn’t seem to go anywhere. Idea what it is? There’s another plug like it waaay off the back of the engine.

Any idea what this plug is by the OBD2?

The cam sensor you have and a gen 3 map sensor plugs are pretty much the same hardshell.
The cam sensor will have a Dark blue wire, a dark blue and white wire and a brown wire.

The map sensor will have a Grey wire, a orange and black wire, and a Green wire.



The map you are using is a gen4 map sensor, the plug you have is for a gen 3 sensor. Easy fix is this


Or you could change the sensor to a gen3 truck map or the pig tail.

The coolant temp sensor is in the correct location for a stock engine and it looks like the little plug on the lower right of your picture is the conector for it. The wire colors are yellow and black or Yellow and tan usually.

Its possible someone built the harness to mount the CTS in the right rear of the engine instead of the drivers front. The heads are the same. You will have an allen head plug in the right rear of the passenger side head. If the conector is back there you can feel free to swap the plug and sensor location.

I don't know about your orange wire, but orange and black are the colors for a IAT sensor if its a dedicated sensor and not built into the MAF sensor. Alot of guys use the earlier maf sensor that does not have an integrated IAT. Its possible thats what its for before the end of it was ripped off as in the picture.

I have also seen some harness use orange for the alt. plug. Which is in a really similar location.
Your last picture=Throttle pedal.
Most common one I see is this one.
wire harness colors

Good luck bud.

Damn, thank you, I can get the whole engine side harness out of the Camaro all the rest of the LS three **** came from so I will have all of those plugs and can line up the wire colors. I would rather keep it all generation four everything because it simplifies.

Didn’t even think of throttle pedal RIGHT by the OBD2 plug

You are most welcome bud. let me know if you need any other diagrams or whatnot. I can usually scrounge up what you may need. I have a decent library of most things LS swap. Sure looks like a cool project. I love the door art on the truck. It reminds me of my dad using an overhead projector to hand paint the family companies logo on the side of all the equipment and trucks when I was growing up. What a wild time.
Looks like you guys are doing great! Keep at it!