This is my first post and really need help. I just had my 91' 3.0 litre rebuilt and the machine shop brought a wire for something under the centre head out at the rear of the motor instead of threw the notch in drivers side head where it belongs. can anyone tell me what this is and if i can run without it. other wise i have to remove the centre head and re route it . really bummed

 

That would be the knock sensor wire. It's a special co-axil cable and believe it to be very expensive. It might effect your timing if not hooked up. I would be highly pissed myself, since it's alot of work to fix this problem.

 

Yeah that's sounds like the knock sensor wire and you should take it back to the shop and have them put it in the right place and at no charge to you. If you run without it it will retard your timing giving you less power. Good Luck

 

Yup, it is the knock sensor wire. Yes, it NEEDS to be hooked up. You need to pull the intake manifold to do it (ask me how I know )

Scottz, you have any other pix of that 46/47 Ford in your avitar? My first truck was one of those (my grandpa bought it new)

 

Yup knock sensor. When I got mine I drove it 400 miles home with a bad knock sensor right after the engine was rebuilt. You will lose alot of power when it's bad and the check engine light come on. Thing about the knock sensor is it's a coaxial cable (a cable that is sheathed) very sensitive and needs to be replaced completely every time the Plenum (intake head) is removed. They need to replace it with a brand new one...free of charge.