Auto Meter 4375 - Manual

Powertrain
Control Module
(PCM)
Oxygen Sensor
Signal Wire
Violet
Black
Red
5 AMP Fuse 12V Ignition Switch
Good Engine
Ground
Connector
INSTALLATION INSTRUCTIONS
2
1
/
16
" AIR / fUeL RATIO mONITOR
®
2650-837L
Installation
1. Disconnect the negative (-) battery cable.
2. Gauge can be mounted in a 2 1 ⁄
16
" dia. hole with brackets supplied.
Gauge can also be mounted in Auto Meter Mounting Cup, or in
Auto Meter Gauges Works Pods.
3. Wire gauge as shown.
Red Wire: Connect to a fused and switched 12V positive source
that is turned on and off with the ignition switch
Black Wire: Connect to good engine ground.
Violet Wire: Connect to oxygen sensor signal wire. Connect to
vehicle wiring harness, not oxygen sensor since some oxygen
sensors use shielded wire.
White Wire: Connect to 12V Dash Lighting. (See Note below)
If your vehicle is not originally equipped with an oxygen sensor,
purchase Auto Meter model number 2244. The heated oxygen
sensor comes with a weld in boss, boss plug, and wiring harness
with a weather pack connector. The oxygen sensor should be
installed in a spot where exhaust from all cylinders flows past
it.The oxygen sensor should also be installed as close to the
cylinder head as reasonably possible so that the sensor reaches
operating temperature quickly. If headers are used, the oxygen
sensor should be installed in the collector. If cast iron manifold(s)
are used, install the sensor in the pipe just below the manifold.
Mounting in the left or right side is acceptable. If monitoring of
both sides is desired, a second oxygen sensor can be used and
a switch (purchased locally) can be wired to toggle back and forth
between both sensors.
The Air / Fuel Ratio Monitor can be used with the following fuels.
fuels
Unleaded Gasoline
Methanol
Ethanol
Propane
Stoichiometric Air / fuel Ratio
14.7:1
6.5:1
9.0:1
15.7:1
OK for use with Nitrous Oxide.
The Stoichiometric Air / Fuel Ratio is the chemically correct
ratio where theoretically all of the oxygen and all of the fuel are
consumed. The mixture is neither rich or lean.
mounting Sensor
Model 2244
Signal Wire
Heater Ground
Heater +
1
12V Dash Lighting
NOTe: “Models with white wire to be connected to 12V Dash Lighting”
Note for Lunar models: Continuous use of lighting, use in excessive heat (over 100 degrees
F.), and use of lighting at full power will reduce the life span of these gauges. It is recommended
that the lighting be wired through the OEM light switch, and that the use of lighting be limited in
extremely hot weather in non-AC cars. It is also recommended that the lighting be dialed down to
less than full power to extend the life of the instruments.
White
Battery
(See Note above)