Looking for any info on my issue at hand.

My 2004 explorer started to misfire, I so far have trouble shot it down to low voltage in the wiring. Im getting 8.5 volts and getting 11.3 volts on all other injector wiring. I traced the wire to the PCM and found that the pin coming off the PCM is only putting out 8.5 volts where all others are putting off 11.3 volts. I have cleaned all connectors and pins, check battery charge and clean leads. Im to the point were I need to send in the PCM to be rebuild but was wondering if any one has come acrross this issue or know of something I have missed.

My understanding is there is always power to the injector and the PCM cuts it off when it injects fuel. Someone else told be that the PCM is just the ground from the injector but since the injector is putting out voltage Im not sure how that is.

Any help would be great.

Thanks
Frank