jonybravo 0 Posted July 21, 2009 Hi all, Not sure if this is getting posted in the right section, just driven down to London and back yesterday and i noticed the speedometer having a mind of its own. It was jumping back and forwards for no apparent reason, for example when I accelerated to 40, the speedo would jump to 80 then down to 60, then up again, and then settle at the speed I was actually going at. Clearly not a good thing not to know how fast you are going, I was thinking perhaps faulty speedon cable? Any ideas people Thanks in advance Quote Share this post Link to post Share on other sites
Reggit 0 Posted July 21, 2009 I don't know what car you are talking about, but iirc, only the early C's with the analogue mile counters had cable driven speedo's. The rest have electronic ones, driven off a sensor on the gearbox. Most likely this is packing up, if the speed reading is fluctuating wildly. A cable at fault usually manifests itself as an oscillating speedo needle, with the occasional jump as the cable snags then frees itself. Quote Share this post Link to post Share on other sites
Supercharged 2 Posted July 21, 2009 What car / year is it... Only really early cars got a non-digital speedo - Sounds like an issue with the speed sensor on the gearbox - about £15 from VW and easy to change. Mobile phones can also cause this behavior - you've not changed where you've mounted it recently etc? Quote Share this post Link to post Share on other sites
jonybravo 0 Posted July 21, 2009 Thanks for the responses. It's a 1994 2L 16V, mobile phone is in the place it has always been, and the mileometer is electronic. Quote Share this post Link to post Share on other sites
Supercharged 2 Posted July 21, 2009 Yeah - I'd try a new sensor ontop of the gearbox then - maybe re-seat the wiring to it before you order one in case it fixes it! Quote Share this post Link to post Share on other sites