The car has been idling rough and there is a smell of gas. I took the car to a Mercedes pro and he hasn't solved the problem. He replaced the fuel distributor replaced with a new one, along with the distributor cap, rotor, spark plugs and wires. He checked for vacuum leaks and found none. The fuel injectors are fine and so is the fuel filter. He had the compression tested as well. What else could cause rough idling?
Check to see if the air filter housing has been sealed properly and that the mass air sensor has not been damaged by dirty air getting by the air filter assembly. If it has, then replace the mass air sensor and clean out the housing and reinstall making sure it seals. The fuel distributor door is normal to leak a small amount of fuel sine it lubricates the door plunger. You may get a fuel smell from this little amount of fuel. If you still need help, a certified mechanic from YourMechanic can come to your car's location to diagnose the rough idle and help you move forward with appropriate repairs.
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