Technical Unsolvable cyl #5 misfire - Tried EVERYTHING


Oct 28, 2017
About injector movement, there is many things that is left to estimations but i did my calculations on highest archievable cylinder pressure as static pressure.
In a engine there is variations on that from combustion peak to intake suction some hundreds time per second.

Other thing is mass of injector to resist rapid movements. Third is to understand what possible very rapid injector house movement effect is to injector needle.

So to the end, i calculated that cylinder peak pressure is too close or even exceed injector spring clamping force and i was not so happy about it so to prevent thread issue of clamping spring bolt, i installed helicois and just stacked 2 springs as a stack.

There is no tool to measure that movement and only trace it can leave is worn injector bore.

To be sure that is not a issue cost was 6 springs from that other head and 6 helicois.

Why i calculated things like this was to find root causes of misfires.
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