Hello all

Firstly, I need to explain that I have since brought this car over to the a.s.s. end of Spain where there are literally no automatic gearbox experts of any make and models for at least a 1.5 hour drive radius. Each garage I have taken it to locally have refused to touch it, let alone quote for a repair. Except one. And the result of that, I will mention below. The car is not overly old - 127k miles on the clock (this would still sell for 5k euros over here in working order!) and just 'enough' dents to earn it Spanish nationality.

The original symptoms
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(1) Speedo does not register at all in first gear, which I then have to overrev it in order to get it to change up into second gear, then the speedo will begin to register the correct speed (for a while).
(2) While driving, the speedo needle will then choose to randomly act as if it's the rev counter, thereby not showing the correct speed but just move up to correct speed then down to zero mph (at will).
(3) Gear shifts are clunky/jerky and not smooth
(4) Fifth gear will not engage, no matter how much I rev it (like I used to do as a teenager in my first ever Fiat Uno Turbo).
(5) Switching over to tiptronic mode makes no difference.
(6) Fuel gauge warning message says "Please Refuel" on ignition start up even though the tank is nowhere near empty. Fuel gauge needle can also randonly go up and down like a tart's drawers while driving (probably doesn't want to feel left out??!!).

The result of taking it to the only garage that wasn't scared
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(1) A Seat engineer (I assume due to the Sharan being identical to the Alhambra) said the codes he read pointed to the G68 internal speed sensor in the auto box. He also said he didn't have reason to suspect the TCM. He checked the oil level and it was ok (apart from the colour of the transmission oil, which he made a point of saying was black and could do with being changed). He cleared the ECU errors which actually made no difference, except :-
(2) I have now also lost reverse gear since picking the car up. And subsequently now have hours of fun pushing a Sharan backwards on gravel in 40 degree heat each time I dare to venture out ....

My question for anybody out there
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Is it worth me first changing the TCM from an Alhambra/Sharan/Galaxy from a scrapyard/eBay (even I could attempt that DIY job) or should I just bite the bullet, attempt a 100 mile journey to an expert and accept that one little sensor G68 could cause all these problems?


Many thanks for any pointers or merely "if it was me, I'd ..." comments

Steve