merc 500 sec runs/ getting some fuel but not all fuel
car starts but sounds like it is only running on 2 0r 3 cylinders only cleaned 3 injectors so only some fuel is getting through because when the engine is running you put your foot flat to the floor and it does not rev.
Not enough info here to guess- "only cleaned 3 injectors"?! anyway, that car is now 30 years old (300 in human years) so it could be anything- you will have to start doing a complete restoration if you like that thing enough, and that is going to get expensive- bear in mind that these were premium cars back in the day- owned by sheikhs, rock stars and F1 drivers- but they are not real valuable now because there were many made- maybe you could start with the catalytic converter, the entire fuel system and the ignition system- whew-
Could be a bad distributor cap, check it for cracks. Also, check the inside for dirty or warn contact points.