Best Way to Get Power Wire Thru Firewall?

M

mtnbiker26

Bike Geek

• Mar 14, 2003

• #1

I'm looking for the easiest/best way to run a power wire from the engine bay into the passenger compartment through the firewall so I can install a stereo amplifier. Does anyone know of a grommet or plug that I can just pop out? The more details the better.

The car is a '03 P5 and the wire shouldn't be any larger than 8 gauge. Thanks in advance.

 

F

FuNwaGoN

Member

• Mar 14, 2003

• #2

yeah on the passenger side there is a grommet that a bundle of wires run through and I just ran my 4 gauage through a slit that I cut in that grommet
it's like up and behind the glove box but you can access it just by crawling underneath there and looking up behind it

 

H

Humvee

Member

• Mar 14, 2003

• #3

This link in the How-To section may be helpful

http://forum.protegemp3.com/vbb222/showthread.php?s=&threadid=4661

 

1

1sty

Member

Contributor

:

2006 Toyota Tundra DC

• Mar 15, 2003

• #4

Use trhe gromments on the drivers side of the car. they are there and are much esier to use then running th ewire to the passenger side.

 

M

myp5ryde

Member

• Mar 15, 2003

• #5

driverside grommet is easier,i agree.you will find this down aroun teh clutch pedal area.makes for a cleaner install

 

F

FuNwaGoN

Member

• Mar 17, 2003

• #6

wELL DAMN NOW YOU TELL ME. j/k guys I ran them through the passenger side and it was a b****. Then after Iwas done I found the grommet on the drivers side. Oh well when I reinstall my new system I will run them through there.

 

M

mtnbiker26

Bike Geek

• Mar 19, 2003

• #7

Can anyone be a little more descriptive about the grommet on the driver's side? I know that there's a white nylon nut type thing by the clutch, but it's the only thing that stood out under there.

 

1

1sty

Member

Contributor

:

2006 Toyota Tundra DC

• Mar 19, 2003

• #8

It is a black rubber grommet that a signifactant amount of factory wires use but it is huge and sits right by the master cylinder.

 

C

cornflaykes

Member

:

07 Mazdaspeed 3 GT

• Mar 19, 2003

• #9

plus the battery is on that side too.........

 

S

seth

Member

• Mar 25, 2003

• #10

damn corn beat me to that fact

 

H

herbieP5

Member

Contributor

• Mar 25, 2003

• #11

I ran mine down the driver side but through the fender. there is a hole by the battery that runs into the fender and down to a gromit under your dash over your clutch. it was easy, you just have to unclip the fender skin and run the wire. then push the wire through the grommit. that was the easiest way for me.

 

M

mtnbiker26

Bike Geek

• Mar 25, 2003

• #12

I found it. Thanks guys.

 

C

chuyler1

goes to eleven

:

2013 CX-9

• Mar 25, 2003

• #13

Just a suggestion...

Run both a power and ground. I have been doing this for my last two installs and it really helps with the light dimming problems. An installer told me about it. Basicly lights dim because your amp's power supply is hogging the ground. Running a seperate wire for it straight to the battery cures this. Adding a cap or two solves the issue of ground resistance, which was why people used to ground to the chassis in the first place. This will also reduce noise cause by ground loops.

If you do decide to do this, it is best to run your power cables over the shortest distance. The farther you go, the more voltage is lost. With that in mind, you should always run the cable up the side of the car that the battery is on.

 

I

iluvmacs

Member

:

2003 Protege ES

• May 10, 2004

• #14

The voltage drop depends on the size of the wire too. Resistance is resistivity*length/wire cross sectional area. You can't change resistivity, but you can change your length/area ratio. That's why I have 4GA. It's small enough to run, but large enough not to cause resistive heating.

 

C

chuyler1

goes to eleven

:

2013 CX-9

• May 10, 2004

• #15

This thread is over a year old. Any particular reason why you felt like resurrecting it?

 

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iluvmacs

Member

:

2003 Protege ES

• May 11, 2004

• #16

Never occurred to me that you all had closed it. I was looking for information about my amp install and read through it.

 

D

DZnutz

Member

:

titanium msp... slight dent =(

• May 11, 2004

• #17

hmmm, this post does bring up some Q's though. i always understood that it was a bad idea to connect the neg terminal of the amp directly to the battery

 

C

cyomega

Member

:

2005 Scion tC, Indigo Ink Pearl

• May 26, 2004

• #18

chuyler1 said:

This thread is over a year old. Any particular reason why you felt like resurrecting it?

Click to expand...

because he is MAZDA TEAM MEMBER of Resurrecting Dead Threads...

But hey, at least it proves he uses the SEARCH feature

 

I

iluvmacs

Member

:

2003 Protege ES

• May 26, 2004

• #19

Of course I do, I hate to waste peoples time.

I'm not part of any MAZDA TEAM though...

 

S

Shane5425

Contributor

:

2011 Mustang GT

• May 26, 2004

• #20

i was warned not to run my 2 4 gauge wires on the passengers side because of the pcm bieng on that side... so i would do drivers side or like i am gonna swap it to down the center consol .. right now it is ran down the drivers side.. i got interfierance from hell becuase of itbecause my amp for my front speakers is ran in the same area..