ok, bought a new sensor for £21, i installed it in less than one minute, and been ok ever since. NO MORE LOOSE CONNECTION ERROR
i bench tested the old one, and it seemed to work when cold, so i can only assume it was breaking down under heat.
so if you get a loose connectoin error, invest in a £21 crank sensor. and if you want pictures of its location then PM me, i took plenty of pics while i was under there!
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