HELP! I am ready to kill something. I am new to mercedes and dont know how stuff works. the car wont start, I spray stating fluid and no change, but if I pull a plug and test for spark it looks fine, pour gas in intake no change, smells like fuel after cranking a while, and I can hear the fuel pump come on for about 2 seconds when first turn on key,tested compression in 2 cylinders and have 112 and 125. It has been down now for almost a month. I tested crank sensor with ohm meter 725, so I replaced cause I saw online it should be 800-1200 put in used one that ohms at 820 with no change, replaced fuel pump relay with no change, replaced cap and rotor and OVP relay with no change. wtf. I dont even know if its fuel or ignition?