I'm reinstalling my LS1 into my 1999 after many months of having it out and rebuilding it. It's all there and done except for 2 engine harness connectors that I can't find where they connect to (incredible, I know). Does anyone know where these connectors go. The first one is from the knock sensor harness - comes off of the 2 knock sensors in the valley area, goes to the rear and plugs into where/what? I can't find it.

The second issue is with a pair of connectors at the rear of the intake. These are not the oil pressure connector, nor the cam position sensor. These appear to be a matched set, with 3 terminals in each plus, and each plug is spaced about 5" apart from each other. They plug into the rear of the intake / engine area. I think I found where one of them goes, into a receptacle at the rear of the intake (slightly to the right of center, towards the pass side. Here's pics I took.

Photos are overall view looking at the right rear of the engine as seen from the passenger side, then zooming in at that area and those particular electrical connectors (pigtails). The single new one is coming from the knock sensors. The other (older) pair - one goes into the rear of the intake, and its sister goes ????

Can anyone assist me with this? Thanks in advance.

1weatherman

TKX.

1weatherman

 

That second pic with the metal clip reminds me of the connector that go's on drivers side and clips to the fuel rail at the back. The others I don't know but what about the crank position sensor behind the starter?
Good luck!
Chris

 

According to my 2001 FSM, the knock sensors go to the PCM. Coming off PCM Blue connector C1 are 2 wires that go to connector C102 (only two pins) which goes to the Knock Sensors. The wire colors are Light Green and Dark Green for the entire circuit.

For the second case can you provide some more info and wire colors? If I understand they ARE plugged into the rear of the intake manifold as in one connector splits into 2?

 

OK, for the second case the only thing that seems to match is a feed from the PCM to the crankshaft sensor and to the camshaft sensor. The FSM connector views also show the metal tabs

Again PCM Blue connector C1 feeds two separate 3 wire circuits.

Crankshaft circuit is Dark Blue/White, Yellow/Black, and Light Green.

Camshaft circuit is Brown/White, Pink/Black, and Red.

See if this matches up with what you have.

 

What color wires are the MAP sensor connector Sam? It's also back there.

 

The MAP sensor is the gray one with 3 pins.

 

The MAP connector is Gray and the wire colors are Gray, Orange/Back, and Light Green

Also, the crankshaft sensor and camshaft sensor connectors are Black.