Hey guys. I recently got a check engine light on my dsm. When I ran it with MMCd it came up as tdc 41 or injector circuit. When I did some reading online I could not find much on this code. I unplugged and plugged back in all the injector harnesses. From what I could see there is no damage on any of the wires. Then I shut off one injector at a time and figured out that all cylinder s were firing. However, while driving my logger was showing knock and I never knock with my current tune and I felt a little power loss. I have no idea what to do next. Any help would be greatly appreciated. Thanks.