It's the fan switch. I broke the EXACT same connector right below the #8 cylinder when changing headers. Now all I need to figure out is where to buy a new connector. I've been running all winter without a fan switch.

 

-The O2 sensor is on the exhaust (drivers side).

-The Fan switch is between the #6-8 cylinders in the head.

-The temp gauge sensor in between the #1-3 cylinders in the head.

-The knock sensor in on the at the bottom passenger side of the block.

Take your pick of which one it is... I know were all of these are because i have installed all of these at least once before.

 

Come on guys, let it die. We know where things are and we know what he broke.

 

Is it the Cold Start Switch?

 

one last post. I have proof but no camera. Went and bought the connector today. Fan switch plug.

 

It is NOT the O2 sensor!!!!!!!!!!!!!!! The O2 sensor (on my '87 IROCZ) is on the driver side screwed into the exhaust manifold.

The sensor in your held is a temp sensor. Just start your car and see what does not register on the dash board.

If its the secondary fan temp switch, it will not show on the dash.

 

It's the coolant temp sender for the dash, I broke that off when I installed my headers and had to replace it.