2007 Mercedes GL450- never know what you’re going to be dealing with on the road

The shop had actually diagnosed a faulty ECU. It was causing cylinder eight to misfire. They had to replace the coil the spark plugs, the injectors, and it still was misfiring. I came out, including ECU for them however, the cylinder eight was still misfiring after extensive wiring test working toward the injector, it was not completely connected. It was essentially causing a misfire after reconnecting. All problem solved.