I need firewall help...please!

[rickinAZ]

I'm planning out my DIYer Bank's Derringer install. As many of you know, I'm more of an aspirational mechanic than a truly competent one. The engine bay stuff seems straight-forward, as does the behind the dash work. The only thing that has me perplexed is getting through the firewall. I can see the traditional entry point, the 2" black plastic circular piece covering a hole, but it looks impossible to access in the Ecodiesel engine bay. There is also the through the fender/door jam appoach, but that won't look very tidy. Thoughts?

Guys, you've never let me down before. help please!

For those that plan to tackle this, here are two how-to videos:

The 1st vdeo shows the firewall portion at the 8:00 minute mark, but their camera angle makes it look way more accessible than it looks to me.

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[chevymitchell]

I'm planning out my DIYer Bank's Derringer install. As many of you know, I'm more of an aspirational mechanic than a truly competent one. The engine bay stuff seems straight-forward, as does the behind the dash work. The only thing that has me perplexed is getting through the firewall. I can see the traditional entry point, the 2" black plastic circular piece covering a hole, but it looks impossible to access in the Ecodiesel engine bay. There is also the through the fender/door jam appoach, but that won't look very tidy. Thoughts?

Guys, you've never let me down before. help please!

For those that plan to tackle this, here are two how-to videos:

It may look hard to get to, the 2" feed-thru everyone uses, but if you take the drivers fender liner out, you can access it very easily.

 

[MCJA]

@chevymitchell is correct - pretty easy to get to if you remove the fender liner. That said, you can reach it from under the dash too. It's a bit of an exercise, but it's doable.

Also, if you use that firewall pass-through, I highly recommend getting a firewall boot. The one linked below fits perfectly into the hole you're planning to use, and it can be used for wire bundles between 3/8" and 1" in diameter. Pretty handy.

https://smile.amazon.com/gp/product/B004K2285E/

 

[MCJA]

Funny... Amazon has a 3-pack of the same firewall boot for the same price as the single:

https://smile.amazon.com/dp/B08LGNDD2G/

Not that you'll need 3 of them or anything, but you can share with a couple of friends!

 

[rickinAZ]

@chevymitchell is correct - pretty easy to get to if you remove the fender liner. That said, you can reach it from under the dash too. It's a bit of an exercise, but it's doable.

Also, if you use that firewall pass-through, I highly recommend getting a firewall boot. The one linked below fits perfectly into the hole you're planning to use, and it can be used for wire bundles between 3/8" and 1" in diameter. Pretty handy.

https://smile.amazon.com/gp/product/B004K2285E/

@MCJA, The hole looks like its bigger than the grommet: 2" vs 1.25". I poked at the black circular cover with a long screwdriver and the edges felt rubbery. Do i have the right one? It's behind the windshield washer tank.

Maybe when I pull the 2" cover off it's covering a smaller hole?

 

[MCJA]

Correct - the plug has a flange that makes it appear bigger than the hole. If you look at that plug from inside the cabin under the dash, you'll get a better idea of how big the hole is.

 

[thance]

@MCJA, The hole looks like its bigger than the grommet: 2" vs 1.25". I poked at the black circular cover with a long screwdriver and the edges felt rubbery. Do i have the right one? It's behind the windshield washer tank.

Maybe when I pull the 2" cover off it's covering a smaller hole?

That's the one. It's got a verticle strip across the center that i was able to grab with a pair of pliers to pull it out. No need to remove the inner fender in my case. But i tend to come from the camp off remove as little as possible... your mileage may vary. I did just order the boot as my wife has complained about the draft at Highway speeds with it open and i have yet to notch and reinsert the original plug.

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