First of all, here’s a photo of the plugs. You’ll notice the plug all the way on the right doesn’t have the same healthy grey coloration of the other three (the first one is darker in the photo because of poor lighting, it actually matches the middle two). Good news, though. I swapped the #4 spark plug and fuel injector with the #1 spark plug and fuel injector, and the engine is running almost right. But I’m still not happy, because I don’t know why it’s running so much better. Until I can prove to myself what’s going on here, there’s no way I’d go up (not that the plane is ready for that, anyway). It’s almost not 100% right, but it’s certainly progress, and I’m pleased about that bit. I may get a little more time on Tuesday to work, I’ll see what I can do then. This is a frustrating time of year to be working on a plane. Life is busy.