I have a 97 tahoe with 130,000 miles runs like new until yesterday drove a short distance less than 5 miles got went into a store came out and would not start , crank nice and fast got good fire and fuel at the rail but would not start after 30 minutes and extended cranking finally started i think it may be a crank and cam sensor but i am not sure is how to check or if there is a way to check . any help is greatly appreciated. ps i better add it just started after i replaced cap rotor plugs fuel filter and two upstream 02 sensors.