Best way to pass thru firewall (amplifier power)

Have you looked underneath the dash from the pedals? Maybe find a grommet to pierce through?

theres actually quite an easy way to do it. there is already a firewall hole right by the steering wheel column and it pops out right behind the battery/air intake filter box.

easiest way to send a wire through is by removing your battery (most people say airbox too but its not necessary with this shortcut). next take a hangar wire or equivalent and make it straight. take your wire and tape a solid few inches worth to the end and then just slowly poke the wire and hangar through the firewall hole, starting from inside the car. should pop through pretty easily, and if you push enough through, it should pop out on the right side of the airbox right where your battery would be for easy grabs with yo fingers.

only other way i know is i believe the way you're doing it, by pushing through from the engine side, but that requires battery and airbox to be removed for enough maneuvering room.

APLPIX said:

Have you looked underneath the dash from the pedals? Maybe find a grommet to pierce through?

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Yes, I've found where the pass thru is under the dash and in the engine compartment but I would rather push from the engine side so I don't have to remove the in-line fuse from the amp power cable I bought. I may just have to suck it up and push thru on the dash side and just reattach the in-line fuse to the power cable once I'm through....

I was very surprised to see how easy it is to find both sides of the firewall, and even to install the new stereo. I'm try to keep the "tear down" of my new car to a minimum, lol.

Thanks for the info OneGoldfish!

I'll have to try it that way tomorrow when I get started on it. So your basically saying that there should be two pass thru points on the firewall? One for that giant bundle of cables and one next to the steering wheel? I didn't see the second one for some reason so I'll have to take a look tonight and see what I missed. I appreciate your help!

What I did since I have a manual car is when you open your door there is a small hole where the windshield meets the dash kind of? It's right underneath your side mirrors and I took mine through that and covered it with a black plastic cover so it isn't an annoying red wire right there in your face, it's a pain getting through that hole so if you wanna say fck it and worry about that another day so you can listen to your subs now you can do that.

OPENyourmind said:

Thanks for the info OneGoldfish!

I'll have to try it that way tomorrow when I get started on it. So your basically saying that there should be two pass thru points on the firewall? One for that giant bundle of cables and one next to the steering wheel? I didn't see the second one for some reason so I'll have to take a look tonight and see what I missed. I appreciate your help!

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we may be talking about the same point, its on the drivers side. i think to the left of the steering column, a rubber grommet with a bunch of wires in black tape going through. thats where i fed my 4awg power through, worked perfectly

I actually used this post from nico to route my power cable through that grommet.

Amp wiring help. : Versa General Chat

Hope this helps!

OneGoldfish said:

we may be talking about the same point, its on the drivers side. i think to the left of the steering column, a rubber grommet with a bunch of wires in black tape going through. thats where i fed my 4awg power through, worked perfectly

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I think we are thinking about the same place. I was able to get a coat hanger through that big grommet on the inside of the car & was able to grab it from the engine compartment. I tried to tape the amp wire to the wire hanger and pull it back through but it kept slipping off and would never come through. I'm only using a 10awg wire so I don't know why it's so difficult to pull it through. Did you feed the wire from the inside into the engine compartment?

Red_Alert said:

I actually used this post from nico to route my power cable through that grommet.

Amp wiring help. : Versa General Chat

Hope this helps!

Click to expand...

Thanks for the post, that makes it look really simple to do! Did you have to get under the car at all? Or could you grab the cable from the engine compartment?

NewNissanNupson said:

What I did since I have a manual car is when you open your door there is a small hole where the windshield meets the dash kind of? It's right underneath your side mirrors and I took mine through that and covered it with a black plastic cover so it isn't an annoying red wire right there in your face, it's a pain getting through that hole so if you wanna say fck it and worry about that another day so you can listen to your subs now you can do that.

Click to expand...

I did that on my last car too. Could you take a pic?

OPENyourmind said:

I think we are thinking about the same place. I was able to get a coat hanger through that big grommet on the inside of the car & was able to grab it from the engine compartment. I tried to tape the amp wire to the wire hanger and pull it back through but it kept slipping off and would never come through. I'm only using a 10awg wire so I don't know why it's so difficult to pull it through. Did you feed the wire from the inside into the engine compartment?



Thanks for the post, that makes it look really simple to do! Did you have to get under the car at all? Or could you grab the cable from the engine compartment?

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I used a flat sewer rod (possibly 1/4" width that my dad owns) that I passed though the cabin out to the engine compartment with my sub power cable taped (weaving around the air box and not taking it out). We then took the sub power cable off, taped my 4 ch amp power cable to the rod, and pulled the rod back through.

This is similar to what I used:
Shop Cobra 1/2" x 50' Flat Sewer Rod at Lowes.com

OPENyourmind said:

I think we are thinking about the same place. I was able to get a coat hanger through that big grommet on the inside of the car & was able to grab it from the engine compartment. I tried to tape the amp wire to the wire hanger and pull it back through but it kept slipping off and would never come through. I'm only using a 10awg wire so I don't know why it's so difficult to pull it through. Did you feed the wire from the inside into the engine compartment?

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i fed the wires from inside to the the engine bay, had probably 6 inches worth tightly taped onto the end of of the hangar, i pushed the rest of the hangar through first and then pulled the wire through from the engine bay. i cant understand why it is slipping off, becuase it worked for me on the first try, handy little trick my dad showed me. however as he was slowly pulling on the hangar wire, i was slowly feeding the 4awg wire into the grommet, so that likely highly reduced the friction issues in that area.