Hello me it is about the engines in the current W204 (safe also in other series, E-Class, SLK, etc.) Who can help me with the following questions: 1. How is the internee designation of Mercedes for these engines? 2. How does the valve actuation (hydropump, cup plunger with Shims etc.) 3. How expensive is a possible valve adjustment? 4. are these engines permanently gas-resistant? (Autogas/LPG) Plan the purchase of a W204 with subsequent conversion to LPG (drive 30,000km p.a.) Thank you in advance for your information Greetings, Eric