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Try tapping the main engine relay - (found in the fuse box in the engine bay)

If this is faulty it effectively stops both fuel and spark - but engine will crank. Tap it with the handle of a screwdriver while someone cranks the engine over - if the engine starts then the relay terminals are shot - its an easy fix just replace the relay. Even if it's not the problem it's an easy test.

Voltage too low at the coilpack or starter motor? Try tightening up the bolt on the earth strap that runs from somewhere under the boot to the power plant frame adjacent to the front of the diff. Then try the earth strap that attaches to the back of the engine near the dipstick.

The NA 1.8 only has the camshaft angle sensor (CAS) at the rear of the engine on the exhaust cam. Check the wiring plug connections to it are all OK.