Mustang 5 (V8) Error code: Injection valve Cylinder 4

Hi guys, my Coyote (BJ 2014) has been suffering a little for over a year. The following problem: Every few months I have the problem that the engine control lights are concerned for a few days or weeks. When I start the engine, it runs noticeably round during the first (approx.) 5 minutes and is much more prone to swabbing. As soon as it is reasonably warm, the problem disappears. When reading out the engine control unit, the following result always comes: Error code P0204 – Injectionve ntil (cylinder 4) – static. But the strange thing is that this phenomenon did not occur once this year for almost 6 months at a time. Now I have it almost daily for about 3 weeks. My workshop, of course, as the first solution, had to exchange the injection valve/nozzle. The whole is supposed to cost 225 euros (125 euros for the valve). The price seems fair, but maybe that’s not the problem. The master had also offered me that I spontaneously before However, the way to the workshop is longer than 5 minutes, so that the error would have disappeared again; possibly until the next day or significantly longer. My question: Does anyone know these symptoms and/or has an idea where the actual cause might lie? (Not that it is on the engine control unit or anything else and I had a new injection valve installed completely for free). EDIT: Vlt still relevant: a few months e before the first occurrence of the problem I had a gas plant installed, because I drive about 35k km per year. While the problem occurs acutely, sometimes the gas plant also refuses its service.