Intermittent miss fire

I have a 2006 VVT Jimny which has a miss fire still occurring after changing plugs, leads, and coil packs. have been told it could be the cam-shaft sensor. Could someone enlighten me how it could be at fault please.

Any engine light or fault codes?
When does it occur, at load or any particular situation or rev/rpm?

No engine light, no codes. Usely under load and sitting at traffic lights

I believe the camshaft sensor determines which cylinder is firing for injector synchronization and coil firing sequence, the Crankshaft sensor sets ignition timing (advance/regard) as a function of the RPM signal. The hardtop M13AA and VVT engine has both which should apply to your vehicle. So the likely problem (but not guaranteed) of a faulty camshaft sensor is a miss fire or cut out, the crankshaft sensor is failure to start or poor economy / performance.
From reading posts on this forum the Jimny camshaft sensor can cause a miss fire when hot, cooling it with water can temporarily restore normal operation until it warms up again. Not sure if you get any fault codes in the ECU though.
Not much else left to change, but always worth a look at engine earth's to ensure they are in good condition, as a poor earth can generate many symptoms and costs nothing to fix.
Good luck
Mike