Hi, I’m a bit perplexed…. Motor M273 5,5 liters, BJ 2007. The engine pats in stand/empty from the intake tract. The noise is therefore irregularly running not in time. That sounds like a slight plop. The engine otherwise runs clean. Keeping the hand on the intake tract makes the noise worse/more frequent. The car was at Mercedes , there was first a spark plug and an ignition coil cylinder 5 replaced. After that three days quiet. Then all the remaining spark plugs and coils replaced. No change. Since he had a sporadic error on camshaft control left (came every few weeks) the magnets camshaft control was replaced. Camshaft gears tested etc. everything well (didn’t now probably render this somewhat amateurish…) . After that everything is good again two days… Now the colleagues with the Latin at the end. Discussion heads off, valves test and so on. I first checked off. I don’t understand why does the car run again – two days? Does someone have a bad idea?