Hello everyone. I have an issue that I hope someone can shine some light on; I took my -10 into the maintenance shop at my local airport for the 500 hour Slick mag inspection and they told be it needed to be replaced. I have a Lycoming IO540 with one mag and an Electro Air electronic ignition. They got a rebuilt mag in, but the threads where the RPM sensor screws in were damaged, so they returned that one and finally got another one in after almost a week of being down. So here is where the issue starts; I do a run up after the install of the new mag. The engine is running rough and the number 6 cylinder is showing a higher than normal CHT, 302 degrees compared to the lowest of 224 degrees, and almost no EGT, 131 degrees. The mechanic rechecked the timing and the mag was timed correctly. He checked the CHT probe and found it working properly. He says that he only took off one lead on the cap, so there shouldn?t be any wire mixup issues. He seems to be a bit stumped about what could cause the CHT and EGT readings. Does anyone have any thoughts on this that could point me in the right direction? Thanks in advance.