[djboen]

I have recently installed a complete new wiring harness, and new gauges in my 48 Aero Sedan. While wiring the gauges, I looped all the ground wires, from gauge to gauges so that I would only be grounding one wire. Then I looped all ground wires for the dash lights. The gauges were working great, and then I noticed that my guel gauge was registering, intermittingly. Then the temp gauge would peg to maximum. I removed the dash, rewired the grounds, and rehooked everything. they would work, and then intermittingly again. Yesterday, while driving the car temp gauge was at full peg, and I turned the headlight switch from dim to bright and I noticed that the temp gauge would fluctuate from normal (175) to max. I set the headlight switch so that the gauge was working. I apparantly am not getting a good ground, but I have checked and rechecked at connections, used a star washer between the body and connector. HELP

 

[tread40]

Wiring Issues

Hello Im Assuming Your Using Electrical Gauges. When You Say You Wired All Grounds Together What Did You Mean? Your Gauges Should All Use One Common Power Wire , The Ground Side Of Each Gauge Goes To Sending Unit.the Lighting System Should Be Separate With Power From Headlight Switch Dimmer And Its Own Ground. If You Have All The Gauge Main Grounds Tied Together Then All Gauges Would Peg Or Be High Due To Resisitance In Each Gauge. Hope This Helps.

 

[docvette]

Doc here, imp:

FIRST, be sure all your gauge wires are PARALLEL wired , NOT SERIES, (looped one Through the other..) a single ground to the gauge from a central ground buss.

NEXT be sure all your power wires are the same from the feed point.

IF correct, you have a Vehicle ground issue, and are getting feedback as the body "Flexes"

GROUNDING:

Run a properly gauged Ground cable from the battery to any handy bolt at or near the starter, From that same bolt get a Battery cable at the parts store, that has two 3/8 ring terminals on each end and attach it there and to the Frame.

Next get some 10 gauge wire and ring terminals and run two wires from your bolt on the block to the Firewall, and the other to the Alternator bracket or mount bolt.

Next get some Wire Braid, (Radio Shack) and install braid from the radiator support to the frame, Fenderwells to frame , hood to firewall, Doors to door posts, gas flap to body, tailgate / Trunk to body.

At each point the wire is grounded, Burnish ALL the paint and grease off to bare metal. Use a proper star-washer and lock. Use sheetmetal or Tech screws where no screws are available.

It sounds like a lot of work, but after you assemble all the parts, it's only a few hours to do..and you'll end up with a system that will work reliably for many years to come..and can eliminate that from your troubleshooting list.

Doc imp:

 

[vicrod]

All of the gauges (grounds) including tach and speedo should be tied together and connected to a chassis ground or ground bus wire (in fiberglass cars).

All of the gauges dash lights should be tied together and connected to dimmer control on the headlight switch.

All of the gauges 12 volt power should be tied together and connected to the ignition switch ON position.

Each gauge will have a sensor connection point. These connection points must be connected to their respective senders and nowhere else.

The voltmeter is simply grounded as described above.
The temp. gauge to the temp. sender.
The oil pressure to the oil pressure sender.
The fuel gauge to the tank level float sender. Make sure the sender is grounded.
The speedo to the speed pulse generator.
The tach to the distributor.

vicrod

 

[302 Z28]

Above is all correct, in addition I would make the voltmeter the fist stop for the 12 volt power, and the ground.

Vince

 

[rgonzales]

amp meter installiaton

need diagram on how wire amp meter

 

[malc]

Eliminate that amp gauge bypass it and install a voltmeter.

 

[T-bucket23]

I have recently installed a complete new wiring harness, and new gauges in my 48 Aero Sedan. While wiring the gauges, I looped all the ground wires, from gauge to gauges so that I would only be grounding one wire. Then I looped all ground wires for the dash lights. The gauges were working great, and then I noticed that my guel gauge was registering, intermittingly. Then the temp gauge would peg to maximum. I removed the dash, rewired the grounds, and rehooked everything. they would work, and then intermittingly again. Yesterday, while driving the car temp gauge was at full peg, and I turned the headlight switch from dim to bright and I noticed that the temp gauge would fluctuate from normal (175) to max. I set the headlight switch so that the gauge was working. I apparantly am not getting a good ground, but I have checked and rechecked at connections, used a star washer between the body and connector. HELP

if you are using gauges that use the metal bracket to hold them to the dash be sure no wires are hitting on the bracket. I have seen this more than once

 

[docvette]

need diagram on how wire amp meter

Doc here, imp:

The AMP gauge goes BETWEEN the source (Battery) and Load (vehicle power wire) in SERIES , not parallel.

Traditionally, the wire that carries power to the ignition buss (usually a 10 gauge red, or purple or orange on the battery cable terminal of the starter solenoid) Is removed and connected to the gauge, the other side goes to the battery terminal..

Some are Vehicle specific, with locations at the Regulator power, and other places..(stock locations) and some have remote shunts, located elsewhere other than the gauge..

I gotta tell ya though, a Volt Gauge is much better and safer than an amp gauge! You don't have Direct battery power under your dash..(that can short on tools watches or rings when blindly poking around up there..) and START a fire that can burn your rod to the ground! AND in some cases, If the shunt burns out (gauge failure) may leave you stranded with a powerless car..

Simple and easy to hook up, One wire to ANY switched , fused Power wire, the other to a properly bonded , hard ground..your Gold! and once you get "used to it" It will give you the same , if not better data.

Doc imp: