Hmmm thanks for that input.

Which begs the question...would the dodgy rev counter signal CAUSE the ECU to pull fuel? Or is a dodgy rev counter caused BY a fueling issue which results in misfire and the misfire makes the rev counter jump? Chicken or Egg scenario there.

I still wonder though what would cause the lean fuel at "tip-in"? That wouldn't necessarily be a cause of low voltage to the fuel pump.