Tacho Query?

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Moderator: martauto

Guest

Post Tue Mar 08, 2005 10:07 am

Ive just noticed that my tacho is now idling at a much lower RPM. Before it used to idle at around 800 - 1000 RPM but now it idles at well under 500 RPM. The car is still running fine with no other apparent issues. I have just had the instument cluster out and replaced the board batteries. Could this have caused the difference? Any thoughts appreciated...
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android
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Post Tue Mar 08, 2005 10:59 pm

You haven't put a 6 cylinder instrument cluster into a 4 cylinder car perchance?
Guest

Post Wed Mar 09, 2005 9:36 am

No it's the original cluster with just the SI board batteries replaced. Good thought though...
cros
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Post Wed Mar 09, 2005 4:26 pm

Did you twirl the needle past ~8k with your fingers while it was open?

The needle can slip on its shaft. You can lift the needle over its stop and push it slightly past the second "stop" to fix this.

A digital rev counter coupled onto a HT lead is handy for this.

8O

Sorry - just noticed you said it read low. That would mean pushing it clockwise (~8k) to fix.

I got a set of metric clocks from germany that underread by a consistant 250RPM until I did the above. Had the correct coding plug (was off an identical car).
Guest

Post Thu Mar 10, 2005 10:41 am

Yeah thanks mate I may have bumped the needle when I had it apart. Although I was very careful! I might try your suggestion and see how I go.
Thanks again... :D