Coolant plug differences?

[DieselRat]

I have an 87 crew cab that I am doing a cummins swap into. When I took out the original TBI 454 I labeled everything as far as sensors etc so I knew what was what. So when the new engine was installed and I was replacing sensors with chevy parts, I ordered a new temp sender for the 454, got the reducer to fit it in the cummins waterjacket, and plugged it right in. No worky. So I did a little digging around and saw a lot of talk about 1 wire hookups for the water temp sender, and sure enough I had a blue wire with sort of a spade connector on it, I grounded the wire and my gauge pegged, remove from ground and its back to 0.

So what gives!! What is the black connector that just happened to be the right plug for a temp sender? What is the actual sender I need to get? Were there 2 different senders for the 454? below are pics of my sender thats installed with the 2 wire plug, and the single spade connector I have open yet.





the wire looks black, its just dirty, its in fact a blue wire.

[DieselRat]

Got it figured out. The sensor I got is to feed the computer its info. The part I need was a sender, that goes to the gauge. Makes perfect sense now, but being that I'm from the fuel injection generation, I never thought about 2 different components when computers and all were starting to be integrated into the trucks.