I’m hoping this experience will help someone else.
Failed my Drive Clean test - high NOx.
Decided to change the oil, put in new plugs, cap, rotor for a start.
When I went to change the rotor, couldn’t access the cam screw so decided to turn ignition key for a few moments to allow the screw to appear in the access hole. WRONG THING TO DO!!! After reading further, they say to turn the motor manually so that the screw will line up.
I put everthing back together and it would crank, but not start.
wtf? Some tuneup. Checked all the fuses.
I put an old spark plug on one of the cables, touched it to ground, cranked the car - no spark. This narrows down the troubleshooting to ignition - not fuel related.
What happens is the high ignition coil voltage doesn’t have a dist. cap so the electricity finds the shortest route to ground - which burns a permanent passage through the coil (you can see a slight burn mark on the side of the coil.)
I tested the resistance of the coil as per the troubleshooting docs, but it measures as a good coil.
Anyway I replaced the coil (about $85CAD) and now it starts fine.
Hope I pass this &^%$ drive clean test soon
Graham