Can anyone help me locate the grommet or hole through which I could pass a wire from the engine bay, forward, into the passenger cabin? I know there's a hole somewhere in the firewall, but where is it?
CATTMAN

 

John..... When they ran my PSE, I believe it was in the upper right-rear section. They needed to pull that right-rear-most panel. (I guess in theory you're running wires in the same path they would have, considering they needed to replace the lower portion of my dash panel).

 

What I noticed when working on Vinnies car is they fed the PSE exhaust wiring through the FAT wiring harness.....you know the one that you unplugged when doing your charger.
Follow it up and you will see what I am talking about!

Stacy

 

The grommet is in the back of the right rear fender space (to the right of the air cleaner). It is way back there and a bit of a dog to access. After cutting a slit in the grommet below the existing harness, I pushed a piece of plastic tubing through from the inside of the car and then used it to pull my PSE wiring back into the car.

 

... and be EXTREMELY CAREFUL cutting or poking holes in the grommet as there is a major wiring bundle passing through there. You do NOT want to cut or nick any wires! Ask me how I know...

It is somewhat easier to access in a cab if you partially raise the top, and release the cables on each side securing the cab top. You can then access it from the interior cab-top area.

 

so is it not really a grommet up in the firewall but is instead that small cavity by the passenger side rear tail light?

 

No, it is a grommet, a fairly large one. It is on the passenger's (right) side rear fender area towards the front of the engine compartment. It is pretty far forward if you are trying to access it from the engine compartment. Shine a flashlight pointed towards the front along the right fender inside the engine compartment and you should see it. There is a large wiring bundle passing through it on the right side, and a small "nipple" on the left (all in the same rubber grommet) you can poke/cut through (be careful).

 

OK, great, thanks. And where does this grommet pass through to inside the cabin? I assume I must remove the rear seats, subwoofer, etc., is that right?
CATTMAN

 

I'm not sure how to access it on a coupe. (I assume you have a coupe and not a cab right?) The grommet is roughly in line with the back of the rear tire, so I think you would have to remove the rear shelf to get at it. The rear seats are quite a bit forward of the area you will be working in, but maybe you have to remove them to get at the shelf? Perhaps someone with a coupe could clarify this.

If you have a cab, follow my earlier post on partially raising the roof. Hope this helps.

 

I think I see the grommet, which if I am right is basically right by the rear tail-light, and not at all at the firewall, where I thought it would be. It's about 3 inches round, rubber, with about a 1 inch bundle of wire loom through it, very tight.

Is that it? Where does it feed through to?
CATTMAN

 

That's it. It feeds through to the DME etc in the rear of the cabin.

 

My Porsche tech recommended against using that grommet, as it can introduce exhaust and fuel fumes into the passenger area. They recommend instead taking out the rear headlight on either side, and passing the wire through the grommet there. They recommended a coat hanger with tape over the end, with the wire I want to pass taped to it, and lubed up with vasoline to allow it to slide easier. It comes out where all the other wires come out: under the rear deck, under the subwoofer, behind the rear seats.

We shall see if this works, and I'll post pics, etc.
CATTMAN

 

Yes, I am resurrecting this old thread, but looking for the same info and hoping for an update.

thanks

 

me too i'm looking for some more guidance and help to get a single wire through into the passenger area. I have a C2S cab.

Help please?

 

It has been a while since I did this, but I believe you'll find the rubber grommet into passenger compartment down almost behind the battery on the driver's side. It is almost at the bottom near the metal that the battery sits on. You shouldn't have to move the battery, but if you have trouble finding the grommet, suggest you move it for a good look.

Oops: Just notice that you're in the UK, so it will be on the passenger side of the battery for you.