Hi, I was reading on one of the forums about S550 2007 several engine models with engine failure (head gasket issue) which I think I have on mine that I recently purchased. It is having misfiring on cylinder #2.I did replace coil spark plugs wires but also noticed my coolant is missing not in oil I think is evaporating in combustion chamber,my question is how do I found out if I have the engine that manufacture replaced on every Benz with that issue or what else it could be I'm not mechanic and I know plenty about cars but can't figure this one out.Thank you

 

Usually, the intake gasket fails not the head gaskets. Only if they used a coolant that wasn't the one specified the head gasket could possibly have had an issue because of the chemical reaction of the two different type of coolant. I had that happen on a car that was supposed to use the red coolant and they used the green when they flushed the system and the gaskets went on both heads. Green foam in the oil was the only way I knew. If your car is using anti-freeze you will eventually damage your Cats. I would think your intake gasket is no, good rather than the head gaskets. You would have fluid in your oil if a head gasket was bad. There is a cheap and easy test to perform and you can even do it yourself. If it doesn't hold pressure, then you might just have a leak in a hose or at hose clamp or the radiator neck has a slight crack (underside usually) and it has all dripped out slowly. Since you replaced the coil and the spark plugs, are you sure that you don't have any other cylinders not function properly? If they did do a recall then I would take it to the dealer and ask. Then I would spend the 125.00 and let them tell you what the issue is. If your car falls within the recall then they will repair or replace what ever is needed without charging you. If you need a head gasket, you will have no choice but to fix it. I would fill up the system with factory anti-freeze and then see if you smell any sweet smell after the engine is hot, then there is an external leak somewhere, that you need to chase down. Also, you can go to the exhaust pipe and see what the exhaust smells like and see if you have a lot of condensation coming from the tail pipe. If the car is running well, no odor will is present and the #2 spark plug could have just fouled because of the coil. If the car is running fine and no fluid is in the oil, then it is an external leak rather than an internal one.