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Speedometer needle bouncing around....

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Old 07-04-2009 | 10:08 PM
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Default Speedometer needle bouncing around....

Just got my car back a week ago from getting the clutch done and yesterday I noticed that the speedometer will delay once I move forward in first, and it bounces around when cruising, anyone have this issue?
Old 07-05-2009 | 01:07 AM
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Sounds like a classic case of bad grounding. Im assuming this is on a late car with an electric sender.
Old 07-05-2009 | 01:17 AM
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Actually, it's an '86, you mean the grounding by the reference sensors?
Old 07-05-2009 | 02:03 AM
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I dunno where the the gauge/sender grounds on the late cars, but i doubt its the bellhousing ground. Anyone else care to chime in?
Old 07-05-2009 | 09:06 AM
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I think 86 cars use the late car electric sender system, which uses an electric speed sensor that drives off the upper front driver's side of the transaxle. This sender and the wiring are easily accessible if you back the car up onto service ramps. Your symptoms sound common for a bad ground, bad connector or faulty wiring in that sender.

Early cars drive the odo from the left front hub?
Old 07-05-2009 | 09:13 AM
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if you tap the gauges will it start working?
Old 07-05-2009 | 11:54 AM
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Checked all the grounds, they are all tight, didn't see any wiring on any hub...
Old 07-05-2009 | 12:38 PM
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Mine will stick at zero, then bouce a bit, if the car's been sitting a while. Tapping on the gauge frees it up, so I've always assumed it was sticking physically, rather than electronics/grounding, etc.
Old 07-05-2009 | 12:49 PM
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Originally Posted by Tom M'Guinn
Mine will stick at zero, then bouce a bit, if the car's been sitting a while. Tapping on the gauge frees it up, so I've always assumed it was sticking physically, rather than electronics/grounding, etc.
+1 thats what mine does
Old 07-05-2009 | 06:44 PM
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i'll try that and see what happens....
Old 07-05-2009 | 08:16 PM
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I have a simliar problem with my speedo. On cold days I can hardly ever get it to work; tapping, smacking, cursing, or praying work get it to work. But ony warm summer days when the cars sat in the warm air for the a while, it will immediately or start up 3 or 4 minutes into the drive. I know it's not anything wrong with the connections to the gauges, so i'm assuming it's probably something with the reference sensor with mine... just need to get around to fixing it.
Old 07-05-2009 | 08:54 PM
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Originally Posted by GuyKeefer
I have a simliar problem with my speedo. On cold days I can hardly ever get it to work; tapping, smacking, cursing, or praying work get it to work. But ony warm summer days when the cars sat in the warm air for the a while, it will immediately or start up 3 or 4 minutes into the drive. I know it's not anything wrong with the connections to the gauges, so i'm assuming it's probably something with the reference sensor with mine... just need to get around to fixing it.
Mine also was dead for 3 or 4 minutes until it got warm, but that never bothered me, I just dont like driving it warm and having it jump between 60 and 80 when I'm doing 70, annoying at best...
Old 07-05-2009 | 10:08 PM
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ive had mine stick a couple times but one tap of the finger on the glass and it jumps to where it should be. never had it gyrating back and forth tho, sounds like an electrical issue to me
Old 07-06-2009 | 07:01 PM
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Tapping didn't work at all, gonna try to see if speed sensor is on tight when it gets cold...
Old 07-08-2009 | 10:03 PM
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Mky mechanic is going to check and make sure the speed sensor is on tight


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