2005 Dodge Stratus Engine

Engine cranks but won't start, there is no connection on the fuel rail to check pressure however when it's disconnected I do get plenty of fuel, there is spark(at least coming from the wires), cam sensor was already replaced, car won't fire with starting fluid(just have it a small "sniff" of the stuff to see if it fired).I did notice that I get no vacuum at the throttle body, kinda oscilates between negative and positive pressure, I was told the car just does going down the road(trying to fix this car for a relative who really really needs this car to find a job), my next step was going to be to pull the spark plugs check their condition and do a compression check, any pointers from there on what to check next or now would be great thanks