Page 1 of 1

2003 Impala Firewall Hole???

Posted: Sun Jan 13, 2008 2:44 pm
by Mikey
Ok, i have done some searching here on the board and have found the plug that everybody is talking about just above the exhaust manifold that usually has the console floor shifter cable going through it, mines a column shift so its just a big black plug. My question is i cannot see it under the dash to feed wires through. i'm afraid that if i accidently poke it out of the firewall from the engine side i won't be able to get to it to press it back in the firewall. I've taken the glovebox out and still cannot find the stupid thing. any help???


Mike

Re: 2003 Impala Firewall Hole???

Posted: Sun Jan 13, 2008 4:17 pm
by FireCpt809
The easiest and most direct way is to drill a hole in the firewall. Under the hood take the antifreeze resivior out. Look at the bottom where the frame rail and firewall meet. cut the insulation. Drill your hole from the engine side.It puts a nice hole right at the top of where the underside of the dash is. Ive done hundreds.. Never a problem make sure you silicone the hole when your done

Re: 2003 Impala Firewall Hole???

Posted: Wed Jan 16, 2008 9:58 am
by motorola_otaku
You can get to it underneath the dash without removing anything.. it's just a bit of a squeeze. IIRC, the big obstruction is the airbox where the heater and a/c cores are, so removing the glove box won't do you any good. You just have to lay down in the passenger-side floorboard and contort yourself some to get to it. ;p

If it stops raining here, I'll try to get some pictures. I have a single run of 4 ga. through the hole with the original plug cut to fit, and it popped back in without too much grief.

Re: 2003 Impala Firewall Hole???

Posted: Fri Jan 18, 2008 7:21 pm
by 007
When I had my 2002 LS I ran 2 8ga, 2 14ga and a speaker cable out through the existing harness on the passenger side floor. There is space around the hard rubber for the wires and a boot on the firewall side that you can poke the cable through and silicone it shut. I had that for 4 years with no issues.

Re: 2003 Impala Firewall Hole???

Posted: Wed Mar 26, 2008 1:12 pm
by rtf01050
there are several holes... when i did my install in my 9C1 the hole was directly in line with where the console would be going in. it is in line with the tranny hump and it is a 1/12 inch hole i believe with a black rubber plug. very easy to run wires through, i had power, 4 strobe cables, and several heavy gauge wires for leds and such.

Re: 2003 Impala Firewall Hole???

Posted: Wed Mar 26, 2008 1:42 pm
by Batwings21
On some impala's there was a hard rubber and foam sound deadener on the inside of the car, so when you popped the black plug out it may be blocked by this. The sound mat had a perforated hole, so you could pop it out with the handle of a screwdriver.

Re: 2003 Impala Firewall Hole???

Posted: Wed Mar 26, 2008 2:02 pm
by FireCpt809
rtf01050 wrote:there are several holes... when i did my install in my 9C1 the hole was directly in line with where the console would be going in. it is in line with the tranny hump and it is a 1/12 inch hole i believe with a black rubber plug. very easy to run wires through, i had power, 4 strobe cables, and several heavy gauge wires for leds and such.

We had a few cars that came in that way. The only problem is the exhaust manifold is about 2 inches from the the wiring and it had melted everything. We drilled a hole where I had said in the previous post and they never had a problem after we replaced all the melted wires.