VOLVO S40 2.4 i "2005" Crank sound when starting the car

[sefofane]

There is a crank sound whenever I start the engine. I took the car to a volvo dealership to check the problem and they replaced the head as a solution, but I can still hear the crank sound everytime I start the engine. The other problem is with the accelerator, there is a vibrating feeling whenever I accelerate. I asked volvo dealership to check the accelerator but they said they didn't feel the vibration. Is there anybody who can provide a solution?