Connecting gauges looking for +/- source and firewall entry
Thread Starter
Le Mans Master
Joined: Jan 2006
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From: Norcal
Connecting gauges looking for +/- source and firewall entry
Without probing the hell out of my car and guessing where to tap I was wondering if there were a writeup or anyone know off the top of their head where to tap. I am connecting a FP and Vac, so I also need a location to enter the firewall safely. Thanks Teddy
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I have just what you need. For $19.95 + $25.00 S/H,, I will send you out one today! 
I installed heated seats and took the 12 VDC feed right off the engine compartment fuse box 12 DC B+ block. To get those wires in to the passengers foot well I went the following route, which was extremely easy and looks just about factory!!
Remove the battery! Below the battery and a little bit inboard, you will find the main harness that feeds the cab. It goes through a rubber seal that you can slide a metal wire through easily. Make sure that it has a smooth loop on it so that you don't tear up anything under the dash. Slide the wire under the seal and crawl in to the passengers foot well and find it.
Attach the wires or a string to the loop on the wire and use it to fish the wires in.
I used plastic armor to cover the wires but you could use the same scheme that GM uses and it will blend right in. You can keep the $19.95.
BC
I installed heated seats and took the 12 VDC feed right off the engine compartment fuse box 12 DC B+ block. To get those wires in to the passengers foot well I went the following route, which was extremely easy and looks just about factory!!
Remove the battery! Below the battery and a little bit inboard, you will find the main harness that feeds the cab. It goes through a rubber seal that you can slide a metal wire through easily. Make sure that it has a smooth loop on it so that you don't tear up anything under the dash. Slide the wire under the seal and crawl in to the passengers foot well and find it.
Attach the wires or a string to the loop on the wire and use it to fish the wires in.
I used plastic armor to cover the wires but you could use the same scheme that GM uses and it will blend right in.
You can keep the $19.95. BC
Thread Starter
Le Mans Master
Joined: Jan 2006
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From: Norcal
Thats awesome thanks for the heads up. I was hoping I can do all this on the drivers side. I know picky guy. HAHA The wires for the gauges are not that long and while I could cut the harness and extend things out I want to tap in the cab for these and drill a hole on the drivers side, to get the harness and vacumn tube in. I'll have to climb in there and see what I can find.
Le Mans Master
Joined: Sep 2003
Posts: 6,276
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From: Farmington CT
Cruise-In VII Veteran
remove the rear driver's side inner fender, cut a hole above the hood release cable
ground to the dash frame, tap into the fat pink on the ignition harness for 12V switched
brown wire on the hatch release will get 12V lights/on
ground to the dash frame, tap into the fat pink on the ignition harness for 12V switched
brown wire on the hatch release will get 12V lights/on
Tech Contributor
Joined: Dec 1999
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
I have anoyher entry area for you. Its on the drivers side BUT,,,I do not have any pictures. Remove the access panel in the drivers side front wheel well (you will need to remove the wheel) and you will find the wiring harnes for the wiper assembly. You can propably get in that way. Make sure that you seal it up with silicone RTV!!
Thread Starter
Le Mans Master
Joined: Jan 2006
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From: Norcal
Thanks guys for the reply. Looks like the route I need to take. Now that I have all the power and tracing nailed down, where the hell is a vacumn source???? My damn VR4 had a million vacumn lines I can't find one on this pig. HAHA
Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
You can install a T in the brake booster vacuum line. there is also a vacuum connection on the very back of the intake manifold.
There is one on the passengers side of the intake for the PCV line that you could T off of.
Bill
There is one on the passengers side of the intake for the PCV line that you could T off of.
Bill
Thread Starter
Le Mans Master
Joined: Jan 2006
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From: Norcal
Thanks Bill. I was just poking around and didn't see any small lines so I figured I would have to go after the brake booster. I'll look in the back of the manifold and see if I can find the line you mention.
Teddy
Teddy
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Tech Contributor
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
THE ONE inthe back of the manifold is a BITCH to get to. It usualy takes removing the manifild to get to it!!!
The small black plastic like with the little rubber 90 deg boot is the one!!
The small black plastic like with the little rubber 90 deg boot is the one!!
Melting Slicks
Joined: Jan 2003
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http://forums.corvetteforum.com/showthread.php?t=994131
I posted some pics in this thread. The interior has dedicated accessory/power/ground wires tucked up above the fuse block. The constant power during cranking comes from the large pink wire on the ignition and routing is easiest through a hole above the hood latch cables. A 1" spade bit cuts nicely thru the fiberglass firewall. The gauges come with a 1" grommet to use in the hole and everything feeds thru it. You can snake a wire over to the fuse panel over by the gas pedal. The lights don't function properly on the dimmer switch because the dash lights are flourescent and the LEDs overload it and shut it all down.
I posted some pics in this thread. The interior has dedicated accessory/power/ground wires tucked up above the fuse block. The constant power during cranking comes from the large pink wire on the ignition and routing is easiest through a hole above the hood latch cables. A 1" spade bit cuts nicely thru the fiberglass firewall. The gauges come with a 1" grommet to use in the hole and everything feeds thru it. You can snake a wire over to the fuse panel over by the gas pedal. The lights don't function properly on the dimmer switch because the dash lights are flourescent and the LEDs overload it and shut it all down.
Thread Starter
Le Mans Master
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From: Norcal
That is great information. Looks like I will be removing a few panels. No problem. I am going to use the pink wire for my draw and will find the ground mentioned. The pink wire I assume is the ignition wire so that works. I am really not concerned with the lighting and will just tap the powersource for that as well. They will be on bright constantly which is what I do anyways. If it bothers me I will assess it later. Thinking about it alittle more will I even need the cranking power??? For what. If I tap off the the interior dedicated power/ground wires That will send power to my gauges. Does the FP gauge require something other then a dedicated power sourced controle by the ignition?
Melting Slicks
Joined: Jan 2003
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Originally Posted by teddyca
Thinking about it alittle more will I even need the cranking power??? For what. If I tap off the the interior dedicated power/ground wires That will send power to my gauges. Does the FP gauge require something other then a dedicated power sourced controle by the ignition?
IQ
Thread Starter
Le Mans Master
Joined: Jan 2006
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From: Norcal
So I will need to put the constant to the pink and the use the other source to turn the gauges on and off so to speak. Without looking at the wiring harness I am not sure what all is involved. I guess I assumed for the vacumn it was a +/- for the lighting and the signal is coming from the tap and the tube. For the FP it was the same and a power source to turn it on. So I will need a constant b+, acc +, and a neg. Just like a car stereo 
Thread Starter
Le Mans Master
Joined: Jan 2006
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From: Norcal
So here is a pretty stupid question. In order to connect the PF sensor to the end of the rail and get pressure, I must remove the little valve deal out of the rail. Like letting the air completely out of a bike. Correct. Sounds stupid but for whatever reason I was under the assumption I was removing the whole thing but it is welded into the rail. BTW I have the ECS connector