spark plug is good but when its plug in to coil on spark
I think you remove one of the spark plug wires from the coil and hold it far apart from the coil. Have someone turn the key so the car is turning over. Bring the spark plug wire closer to the coil and if there is spark the coil is good. Note: if you hold to close you will get a very good jolt of spark if the coil is good, that is why you start far away and work your way closer.
start with checking the fuses, coil wire, distributor cap and rotor.
try to get a new ignition rotor
The spark is always blue. If your coil is bad your engine will misfire.
Why start with the module? The coil is is a good place to start. Make sure of course you have voltage at the coil, if not trace it back.
You will still have spark, car will try to start or backfire. If no spark at all the plugs see if you have GOOD spark from coil. If coil is working then you will find the problem in between the coil and the plugs, probably a distributor component issue. The ballast resister is a possible cause also.
If you have access to a spark tester, use it. Otherwise, remove the spark plug, reconnect it to the spark plug wire, and rest the tip or threads on a good engine ground, AWAY from the spark plug hole. Attempt to start it, and watch for spark. If none, replace the spark plug and try again. If still no spark, the magneto coil may be faulty.
it could be the coil pick up in your distributor
Is there any chance that your fuel has water in it? This happened to an older vehilce of ours and while there was what appeared to be fuel at the injectors, it was too watered down to allow the vehicle to start.
Check spark plug wires, distributor cap, and coil for cracks that let moisture in.