01-08-2020, 05:22 PM
(This post was last modified: 01-08-2020, 05:23 PM by andrew34ruby.)
To me, this sounds like an HT fault. The High Tension voltage that needs to reach the plugs and create a spark.
Under load the pressure within the cylinder increases. At higher pressure the voltage needed to jump the plug gap is a higher voltage.
If there is a crack in the rotor arm, or distributor cap, or the coil neck or even the spark plug, then the current will take the easiest route. At low revs and not under load the easiest route is likely to be to jump the plug gap and ignite the mixture in the cylinder. At higher revs, and under load the voltage to jump the plug gap increases so there is more chance of a short circuit of the HT through some crack somewhere.
Under load the pressure within the cylinder increases. At higher pressure the voltage needed to jump the plug gap is a higher voltage.
If there is a crack in the rotor arm, or distributor cap, or the coil neck or even the spark plug, then the current will take the easiest route. At low revs and not under load the easiest route is likely to be to jump the plug gap and ignite the mixture in the cylinder. At higher revs, and under load the voltage to jump the plug gap increases so there is more chance of a short circuit of the HT through some crack somewhere.