View single post by Mark Rosenbaum
 Posted: 05-02-2007 06:21 am
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Mark Rosenbaum



Joined: 03-12-2005
Location: Kingman, Arizona USA
Posts: 532
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 If the measured coolant temperature is circa 160° the gauge should read a needle's width (roughly) below mid-range.  If it does not, the first thing to check would be the voltage stabilizer module mounted to the forward face of the instrument pod near the fuel and temp gauges.  Normally the stabilizer produces a pulsed output that over time averages to about 10 volts; there is also a solid state version that produces a constant 10 volt output.  When a failure occurs, the stabilizer may produce a constant 12 volts, which would result in a high reading on the temp gauge and on the fuel gauge.

The temp gauge or temp sensor could be defective, but a failure in either tends to result in a dead gauge rather than an inaccurate one. Similarly, if the wiring is defective, the gauge quits operating.  Note that a previous owner might have adjusted the fuel level sender to mask the inaccuracy of the fuel gauge due to a faulty voltage stabilizer.  Further, while it is possible that a PO might have mis-calibrated the car's temp gauge, that requires a level of foolishness very rarely seen.

Drain the engine coolant before removing a temp sensor.  For installation, the case of the sensor must connect to the metal of the engine block, so one should use a sealant such as Permatex or Hylomar rather than plumber's tape.