2004 D12 465 threw a MID 128 SID 1 FMI 3 code

Today I was motoring down the highway when suddenly my truck started to lose power. I'm guessing it was de-rating itself. The check engine light came on, and a message to check ECU at next stop. I limped a few miles to find a safe place to pull over to checked it out. The engine was idling with a definite miss and I retrieved this code: MID 128 SID 1 FMI 3. I shut the engine off and restarted it a couple of times to see if i got any other codes, but got none. I shut the engine off for about 5-7 minutes while I walked around kicking rocks, trying to figure what I was gonna do next. I decided to start it again to see the temp and oil pressure readings, and it ran fine. I drove 60 miles home without a glitch. Can someone decipher that code, and help me figure what is happening here. I just put this truck on the road a week and 1500 miles ago. There were, to my knowledge, no codes of any kind stored. Truck has 840K miles, and I did change out the alternator four days ago. Any help would be greatly appreciated. Thank you.

 

I noticed there is the dreaded oil leak at the injector harness pass thru. I,m wondering if this maybe related to my problem. I did the injector harness splice on an '06 a couple of years ago, but it
had no other issues other than the oil leak. I wonder if I'd be better served if I replace the entire harness , fixing the leak and the injector issue at the same time. Opinions welcomed. Thanks.

 

Thanks nasriza. One more question please. So the coil on the injector is shorting, correct? I did 400 miles today with no problem; would that explain why?

 

Thanks for the advice. Is injector replacement a job for the professional? I've never changed injectors, but I feel I can do it. I just don't have any special tools. (Volvo specific). Will truck need to do on computer to program injector to ECU? Thanks