What all is grounded to the back of the air intake manifold on a 91 pontiac firebird 3.1L?

I was checking my fuel pressure and I decided to look around and see if anything is loose. One of the nuts that holds several wires to the manifold was loose (which is disturbing, I'm a poor mechanic it would seem) but I was curious if anyone knew what these wires were? I assume they are just to ground the manifold to the chassis.

Now with that aasumption do you think that if my intake manifold was poorly grounded that it would cause my car to have a hard time starting? After I rebuilt my engine It was running good but lately my care has been starting then dieing almost immediately. I have to repeat several times to get the thing running. I've replaced just about everything I can think of so I'm wondering if this was my problem? Anyrate I guess I'll know when I drive to work tomorrow!