mistyq wrote:what do i check resistance across the two terminals or each terminal and to earth.
oops my mistake, it's not earthed

. Measure it across the two terminals.
(One thing i did notice with both the cam pos sensor and crank sensor the wire from the sensor to plug is very stiff like like the outer sheathing has burnt and gone brittle but im sure this won't affect the copper inside sheathing?.)
IIRC the sheathing is usually very stiff, but if it's damaged I suppose it could affect the shielding which could give rise to extraneous signal noise. That is what an oscilloscope would tell you.