advice or info

Hi guys, im new here. I'm in facebook w204 group but is useless lol. So recently I bought my 1st Merc it's a 2008 w204 c220 CDI SPORT. Love the car and all, but been told the engine suffer from chain and injector problems? I have a documents from where when it was new, it says i got 646 engine...

I have had my 2007 E320 CDI about a month now & the only fault I have found so far is the fuel gauge. It shows empty & reserve light on but only takes 40Ltrs to fill it, ( it has an 80ltr tank) the gauge then only shows half full. I was suspecting the tank sender but doing a search throws up...

I am looking at a '91 SL300 24v sport.Can someone tell me please- (1) what does sport mean? (2) is lack of aircon normal or unusual? (3) is cruise control standard? (4) will it have a 4 or 5 speed autobox? (5) is there anything in particular I should be looking for in terms of faults? It...