Check Engine Code1239: Shows #6 Fuel Injector Short / Fuel Pump

On a 2004 Isuzu Rodeo - Direct Injection Engine shows 50% Power Loss and the Check Engine Code1239: Shows #6 Fuel Injector Short AND Fuel Pump (High Pressure) problem. I have replaced the Injector and it still shows 50% Power Loss with #6 Cylinder continually missing. Can a High Pressure Fuel Pump cause a missing #6 Cylinder? I’ve already had two compression tests done (125-130 pounds) but still nothing??? I hate to spend 500-900 dollars on a Fuel Pump and it still does the same thing.

Thanks in advance.

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