tacho,fuel economy guage not working

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mikex1
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Joined: Tue Jul 15, 2014 1:19 pm
Location: barossa valley

tacho,fuel economy guage not working

Post by mikex1 »

Hi big coupe members,stay safe out there, My tacho,fuel economy guage stopped working on weekend, never had problem before,is fuel economy guage run off vaccum line,possible disconnection. The tacho would be digitial,is there easy fix to recify fault, thanking you mikex1
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hornhospital
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Re: tacho,fuel economy guage not working

Post by hornhospital »

The tachometer operates on the ignition pulses from the ECU. The econometer compares injector pulse time to ground speed and calculates fuel economy. There is no vacuum involved.

Most likely the cluster has lost connection in the sockets at the back of the instruments. They are notorious for just that. Take the cluster out and treat the connections with contact cleaner.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
GRNSHRK
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Re: tacho,fuel economy guage not working

Post by GRNSHRK »

Thread moved to the "Interior" forum by board moderator :-"
:mrgreen:
Bobbo
1980 633 CSi Cypress Green/Pearl Beige
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2005 330 Ci ZHP Cabrio Imola Red/Bone/Black
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Slownrusty
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Re: tacho,fuel economy guage not working

Post by Slownrusty »

I agree with hornhospital.

I recently removed my gauge cluster to replace the broken odometer gears. After I re-installed the gauge cluster and started the car, the gauges starting acting crazy, so I removed everything and re-seated the blue plug (shown below) and that cured the erratic behavior.
Odometer Replacement 2.jpg
Odometer Replacement 2.jpg (71.94 KiB) Viewed 2246 times
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