Tempature Gauge Problem with Rally Gauges
Short answer: A temp gauge that jumps/pegs on start-up and then reads cold is usually the old idiot-light “test” wire left connected — the wire from the ignition that lit the temp warning light at start. It’s the harness connection with two wires going to one point (often green). Disconnecting it (per the rally-gauge install FAQ) cures the pegging.
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Content last modified: June 13, 2026 at 10:06 am
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