Fuel Pump problems of the 2002 Mercedes Benz C Class

I purchased a 2002 c240 mercedes in 2006. The car has never given me any major problems until here recently. The car began to not start and completely shut down. I had to have the car towed three times to the mechanics (don allen service center on allentown road, fort washington, MD). Was told I needed a fuel pump. I paid $1,500 to have a new fuel pump installed. Problem not solved. When I tried to start the car. It hesitates for about 10-15 seconds before it turns over. I took it back to the mechanics and was told it needed to fuel filter changed again. Problem not solved. Now the car makes this loud whining noise from the back of the car. Now I have to take time off from work to take the car back to the mechanics to have him to replace the fuel filter again. This is what I'm being told is the problem with the car. The fuel filter is not working properly. This will be the third time in one week that the fuel filter had to be changed. I was told that once the fuel pump goes bad, the car will never run the same again. I believe this to be true considering the problems I've encountered after having the fuel pump installed on my car. Having a mercedes has been a headache with the cost of just maintaining the scheduled maintenance which is costly. I plan on going back to a Lexus after all is said and done! thoroughly disappointed with mercedes. These vehicles should be recalled to fix the faulty fuel system/pump/filter. I plan on reporting this complaint to my states attorney office in the state of maryland, prince georges county.