I've had the p0341 code before. I also had a big problem with p0300 random cylinder misfire. The car didnt misfire but the computer thought it was misfiring on 1 and 4. Plugs, wires, coils, and the module were all new. I had to do a crankshaft variation learn procedure on it with a tech 2. I work at a gm dealer so luckily I have access to their equipment.