Where is there a place to run wires through the firewall on a 98 Z-28 camaro? I've looked but can't see a thing under the cowl, would the ECM harness have enough room to sqeeze a few wires in through the firewall grommet?

 

Best place is behind the computer. There is more than enough room to run a few wires. Christ, I ran 2/0 welding wire through there when I relocated my battery and that stuff is thick, like 5/8" thick.

 

On the passenger side footwell there is a large 2" or so grommet where a wire already comes through. I've run my fan switch and line lock wires through there. You have to pull the ECM underhood to get at it from the engine side.

 

what he said. If u rip up the carpet and passenger kick panel u can get to it (dont have to tear ALL the carpet out, just in that corner) . OR you could unbolt the PCM which is held in with 2 -8mm bolts and move the pcm out of hte way and see the grommet directly through the hood.

 

You don't have to pull up any carpet. Just pull the panel down that covers the underside of the dash and you can see it up in the far corner.