Help. What is the wire that is grounded to the header bolt on 90 mustang?

[90lxwhite]

I just changed valve cover gaskets so I had intake off and when I put it back together it is stumbling and chugging at idle. Im pretty sure I have the vac lines hooked up right the only thing I can think Im missing is there was a wire that was grounded to the passenger side header bolt I do believe, well now I cant trace that wire down to ground it. Do yall know what that wire is? Please help. Im outta town and need to leave tomorrow.

thanks

mike

 

[Rick 91GT]

From the factory nothing is grounded to a header bolt, there is a braided ground strap that goes to the rear of the lower intake stock, and there is a orange wire that comes off the injector harness that also needs to go to ground.

 

[rockyracoon]

yes as rick alluded to maybe someone had the o2 sensor ground hooked up there (orange wire) That wire needs to be grounded for proper 02 sensor function.