Weird speedo on my 90GXE

My 90 GXE's speedo has been acting weird the last few months. When I start up either in the morning or after it's been sitting awhile, the speedometer will register speed while standing still. Either in Park or when I shift into neutral, rev the engine, the speedo registers speed as if I'm moving. When I put into Drive with foot on brake, it still shows that the car is moving. The odometer also registers mileage as I can see it slowly turn! After the car's been driven some, the speedo will sit back on 0 when I come to a stop and behave normally. This happens everyday- it's not just an intermittant occurence.

Any thoughts??

Chris

90 & 94 GXE's
Reply to
Chris H
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Could be a bad head unit or a wacky speed sensor. Never seen one doing what you're talking about. From what you describe, my guess would be a bad head unit.

Reply to
Steve T

The speedo unit is the first point for the speed sensor signal, there is some processing done by the speedo unit (sine wave signal is squared up and frequency divided by 8) before the signal continues on to the ECU/TCU etc, the odometer motor is also driven off the speedo assy.. I think it would be unlikely the speed sensor is faulty in this case, as it is a mechanical device, sounds like you have a problem with the speedo unit itself, can't be too much more help than this.. sorry

Greg.

Reply to
Greg Stewart

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