Hello all, new member here. Can anyone tell me if PEM part numbers are interchangable. My 04 S60 2.5T AWD VIN 397999 with 175,000 miles is having fuel delivery issues. I've already switched out the FPS on the fuel rail. PEM is located above the fuel tank. Getting various cylinder misfires and a P0089 code. I'm unable to find a used PEM with the proper part #30636431 but part #30769225 is readily available. What is the difference if any? I would rather avoid having to buy new. Any assistance would be appreciated.