I have a 1985 190E 2.3 with over 300k miles on it. Suddenly yesterday as I was leaving Stanford, my car felt heavy as I tried to get the car into motion. (I have a 5-speed tranny). Upon starting the engine, I noticed a loud, deep throttle nose. And as I revved it, the nose got louder and the revving got tougher.
The timing doesn't feel like it's missing, but the idling is really rough. I've recently changed the fuel distributor, fuel injectors, fuel filter, spark plugs, air filter and water pump.
I left the car parked for about 5 hours and started it back up again. This time, the car really lagged on 1st gear. However, after driving on the freeway for about 40 minutes and coming to a stop sign, the car doesn't feel that heavy on first gear anymore, but still doesn't feel the same. Highway driving isn't as bad as starting on first gear. Having the car parked and revving it would result in this "heavy" feeling.
Does any of you Mercedes guru have any clues? The only thing I can think of is a sticky valve. Any suggestions would be great.