Ford Fusion (2002 - 2008) - 03 1.4 Speedometer wobble

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Wed 22 Jul 2009 17:57
03 1.4 Speedometer wobble - jcp
The speedo bounces, wobbles, and overreads, then settles down for a while, before starting off bouncing again.

I am fairly sure it has an electronic speed sensor fitted to the transmission in place of an old-style speedometer cable (but there is no Haynes manual for the Fusion ? they say to use the Fiesta Mk5 one instead).

The bouncing speedo problem may have started when I changed the clutch and had to disconnect all the cables etc from the transmission/gearbox area. I had difficulty disconnecting the speedo cable connector, so I removed the whole sensor (as if an old-style cable). The sensor had been bound in foil tape, which I unwound before removing the sensor. I rebound the sensor with the same tape on re-assembly.

I suspect the bouncing is because either the sensor is dirty or damaged, the cable connections are dirty or broken, or the tape binding is inadequate. I have briefly tried re-attaching the cable connections and re-binding the sensor, but got no improvement.

Before I try replacing the sensor itself, I would be grateful if anyone had any suggestions, or knew how to find what is really wrong?

Note: it is not a "cable" that turns in a sleeve - it is an electrical wire ending in a plug connector (that I couldn't see how to separate so I had to take the whole sensor out). The wire may be broken and making only intermittent connection (but I don't think so). I wonder more if the foil tape is not shielding the sensor properly (or something like that)!

Thanks

JohnieBoy
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Wed 22 Jul 2009 21:28
03 1.4 Speedometer wobble - elekie&a/c doctor
I would think that as the problem seems to have started since the gearbox removal,then either the sensor has been damaged or it is not seated correctly in the gearbox and thus giving an erratic signal.The foil tape/sleeve is usually fitted as a shield against hot components.eg exhaust.hth
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Fri 24 Jul 2009 20:23
03 1.4 Speedometer wobble - jcp
Thanks
Sounds like its not a problem with the tape, so I'll remove the sensor again and check it out.
John
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