2010 Cylinder 1 Misfire, Cylinder 1 Tube Surface Rust
So I have been trying to track down the cause of this misfire for a bit now. Swapping coils did not correct it. I have replaced all plugs since the B5 service was due and I noticed that in cylinder 1, the cylinder supposedly misfiring, there was surface rust on the tube. There was no signs of white coolant crystals in the tube and the plug that came out looked fine, no indication of burning coolant and there is no coolant loss on the vehicle.
I am wondering if anyone has seen this surface rust on one cylinder before and has any inkling as to what is causing it? I am going to swap injectors next to see what happens. I heard these have intake gasket issues?