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MikeKey
17-06-2007, 02:59 AM
The plan was to move my XBox from the footwell to the boot today so, as it would involve routing power directly from the battery to the boot, I spent last night scouring the forums for information on how to get wires through the firewall.

There were a few different ideas, some more popular than others, and some requiring holes to be drilled which I wasn't really keen on.

Here's how I did it, based on the "through the wheel arch" method suggested by Gly & Mpau009 (http://www.clubvr4.com/forum/showpost.php?p=161442&postcount=4), plus a bit of extra information you might find useful if you do anything similar. Note that I have a N/A V6, but it should work just as well with VR4s and other models. As WODJNO says (http://www.clubvr4.com/forum/showpost.php?p=161691&postcount=10), this should also work on either side of the car.

First, I had planned to use some 14 guage wire which would be just right for the M2-ATX power supply in my XBox (fused at 10A). The company I ordered the wire from sent the wrong stuff, however, so in the end I went for one of those amp wiring kits off of eBay.

I ended up paying £12.99 (NZ$34 /Wyhy) for a 1000W FLI kit (http://www.fliaudio.co.uk) (10 guage) which will easily handle the XBox. At that sort of price you can't go wrong, and you're saving yourself the bother of re-wiring to cope with more boot gadgets if you decide to fit them later on.

Preparation

Step 1:
Make sure you have enough wire! Once through the firewall, I originally planned to route down the side of the transmission tunnel, under the back carpet and seat, then into the side of the boot. If you do this, you'll need at least 6m of wire. As I only had 5m, the only choice was to use the trunking along the door sills.
Having tried both ways, I'd recommend using the sill trunking, although you may have trouble if you're running really chunky wire.

Step 2:
In the cabin, remove the plastic trim from the left side of the transmission tunnel/center console. There were 3 metal screws, one just inside the top right of the glovebox, one just under the bottom right corner of the glovebox, and one hidden under a little plastic cover in the foot well. There is also a plastic retainer to remove slightly further back in the foot well, just remove the plastic screw and this will pull straight out. The rest of the trim is just held in place by tabs so you'll need to pull it about a bit to remove it.

Step 3:
Empty the glove box then, with it almost all the way open, pull the little stopper tab on the left side towards you. It's a bit fiddly to get at the tab, but it should just pop out towards you and allow you to swing the glove box all the way down to rest on the floor:

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Step 4:
Jack the front left of the car up and remove the wheel. As always, make sure you support the car with axle stands or something else, don't just rely on the jack or on you own head (legs?) be it!

Step 5:
Remove the screws and 14mm bolts securing the plastic wheel arch liner, detach it from the bodywork, then gently bend the right side down out of the way so you can see up into the top right of the wheel arch (as you look at it from the side). There were 9 bolts/screws keeping the liner in place, and a helluva lot of cack lurking in all the joints and crevices back there!

Wiring

Step 6:
Feed the "boot end" of your wire through the rubber ABS sensor grommet in the rear right corner of the engine bay (as you look at it from the front). This is a bit fiddly at first, but it's easy once you've got the end in... ooh err! It goes without saying, but make sure you leave enough wire in the engine bay to reach whatever it needs to reach!

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Close up:

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Step 7:
Here's how the wire will be routed in the wheel well. It comes out of the ABS sensor grommet (point A) and feeds into the door pillar grommet (point B):

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Cut and remove any tape from the door pillar grommet, being careful not to damage the grommet itself. If you leave the tape on, you won't be able to stretch the grommet enough to get your wire through. You should leave the tape on the wiring loom, however:

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Step 8:
Grab the top part of the grommet (marked in red on picture above) and pull it open enough to get the end of your wire in. While holding the grommet open, feed enough wire in so you can grab it on the other side, maybe a foot or so.

Step 9:
Pull the remaining wire through the grommet from the inside. If you can't see the end of the wire, try feeding some more in, or remove the oval insulation piece stuck to the grommet mounting for better access:

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Close up:

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Step 10:
Check you have enough wire length in the engine bay, then zip tie up anything dangling in the wheel well and tape up the door pillar grommet again.

Step 11:
Refit the wheel arch liner and wheel, let the car down, then finish routing your wire wherever it needs to go.

Job done! :scholar:

pitslayer
17-06-2007, 01:09 PM
you know there is an easier hole to go through.
from the battery go straight the firewal, then go across to the drivers side. there should be a hole there which doesnt look big enough to get any thing through, i got a chunk of massive wire through, just keep pushing, and it will come out just above the accelerator or clutch pedal, it can then be taken down into the center console, and run all the way back to under ther drivers side. then under the carpets, up under the rear seat and into the boot

looks good what you done there, just seems like a massive effort lol

MikeKey
17-06-2007, 02:41 PM
Hi pitslayer,

Is this the hole you mean?

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If so, it didn't look like there was enough room there to get a new grommet and both wires through, and not using a grommet was definitely not an option.

The only other hole I saw was the one with the accelerator cable going through it, and I wasn't going to mess with that! /pan

Cheers,

Mike

Gly
17-06-2007, 08:40 PM
theres also a hole behind the battery... goes striaght into the guard...

good for the massive 50mm^2 cable i ran thru :D

peter thomson
17-06-2007, 09:20 PM
theres also a hole behind the battery... goes striaght into the guard...

good for the massive 50mm^2 cable i ran thru :D

Used that one today as well to run a wire for an amp and then through the one shown above

Roberto
17-06-2007, 10:44 PM
The hole I used is about 3 inches lower than the one in the last picture, I saw this and rejected it, but then had a eureka moment when I found the other.

Simple clean clear hole leading to the back of the center console.

Nutter_John
17-06-2007, 10:51 PM
One thing to point out is that the route refferenced by Mike is the best as it does not go anywhere near the heat areas within the engine bay . On the VR4 the rear turbo and the area around it can get very very hot

But the whole Roberto is mentioning sounds like the entrance for a clutch on the manual

pitslayer
18-06-2007, 01:12 AM
yeh it was somewhere around there and it got massive chunky cable through, used for industrial electric batterys/electric machines, used mainly on the 48volt machines

Roberto
18-06-2007, 11:03 PM
Only problem with that statement Nutter is.....

I DRIVE A MANUAL.../pan

Atik
01-01-2010, 12:58 AM
Why have I only just seen this thread today?!? In my multiple searches previously on how to thread a cable through the firewall, I never once saw this thread :(

Anyhow, with the SUPER helpful pictures posted here, I was finally able to run some 4 gauge power cable through the car for the amplifier.

I would like to make a request for one of the mods to change this thread into a 'how to' article, as it was VERY helpful and detailed.

Turbo_Steve
01-01-2010, 01:25 AM
Er....wow....this is the hard work method!

I did exactly this, going under the wheel arch etc, but rather than pull the glovebox out etc, I simply threaded it in from outside the car using some thinner cable as a "pull". It then ran up the passengers side of the car.

Gravity is your friend.

Atik
01-01-2010, 01:43 AM
I did end up using some thinner cable to thread through, but only cos there was so much stuff in the way once the cable actually got into the cabin. and it being 2-3 degrees celcius outside, everything was frozen in place and wouldnt flex/move. Managed to thread it all through the passenger side in the end. Now I need to get hold of a proper battery + terminal block cos I got so many things wired up!

Dom B
01-01-2010, 02:21 AM
The passenger side grommet behind the liner is by far the best way as shown here. Makes t very tidy and the grommet has not a lot using it. the drivers side is another story though that one is bristling with multipin plugs so if you had to route a sensor etc in there it might be a fiddle. Looks like there isn't too much space. i always expect the rear washer pipe connector to pop and leave me with a wet foot!

Wobble
01-01-2010, 03:44 PM
will be attempting to do this myself in the near future,lets see how it goes

Klasman
01-01-2010, 08:57 PM
Got som great help from these pics did it today :D

Getting the cable trou the B grommet in pics was hell imo, didnt do the smaller cable thingy... used a bent antenna to pull the cable to me dont do it if you have a bad temper.

Turbo_Steve
01-01-2010, 09:10 PM
I have a stinking temper, and it was dead easy using a stiff rod (coat hanger) taped to a thinner wire (16awg) taped to the 4awg I pulled through.

It's a LOT easier to go through from the outside to the inside, though.

Did you make a little cut in the grommet with a knife first?

Klasman
01-01-2010, 09:35 PM
Ye i did but i still went rambo on it....

Well it worked eventually :)