N55 Valvetronic Advice Needed. I have a 2014 435i (M Sport) with ~30k miles. As you would reasonably presume from the relatively low miles, I don't drive the car very much and didn't drive it at all for nearly two months during the state mandated COVID-19 lock down. Unsurprisingly, after nearly two months of not having been driven, when I I have a 2013 335i with M-Sport and 6 speed manual trans. Since purchasing my 335i I’ve put on 100,000 miles with the car having a total of over 115,000 miles at this stage. So far I’ve had the following major repairs under warranty with zero out of pocket cost: - Manual transmission replacement at 56,000 miles (common 2nd gear synchro Carbon buildup is a common issue in pretty much every direct injection engine so it’s not exclusive to the BMW 3-Series. However, the N54 engine used in the BMW 335i from 2006 to 2010 is more prone to excessive carbon buildup than other BMW engines. This was BMW’s first mass-produced turbo engine and was plagued with many issues. VANOS solenoids, valve cover gaskets, oil filter housing gaskets, and water pumps should basically be considered standard maintenance. Many of these issues pop up around 100,000 miles. In general, expect F30 335i models to be pricier to maintain and repair when compared to the 320i, 328i, and 330i. BMW F30 335i Reliability . F30 335i Tuning & Mods Changing the ECCENTRIC SHAFT SENSOR resolved my rough idle at start-up issue. Had it fixed in late 2018 and it has not come back. Dealer wanted $1800 but found a independent that specializes in BMW's who did it for $900. The shop was very familiar with this problem as it is a common failure. It seems the seal fails and oil gets into sensor. The BMW F30 3 Series Sedan 335i has a Inline 6, Petrol engine with 2979 cm3 / 181.8 cu-in capacity. The four most common problems with the N55 are, in no specific The ignition system is one of the first places to look if your BMW 335i is not starting. There are primarily two components of concern at such times – the ignition coils and sparkplugs. The deformation of sparkplugs is one of the most common causes for the engine not starting despite a working fuel pump, battery and starter motor. The dual-mode ECU-controlled valve exhaust from Akrapovič offers stock-level sound at normal cruising, and a joyful deep sporty note when driving the 335i more dynamically. The Evolution systems replace the stock exhaust from the catalytic converters back. Mountable for: 335i Limousine (F30) 335i xDrive Limousine (F30) 335i Touring (F31) ZZ5CB.