I have a 94 E320 with 104,000 miles. New spark plugs from Fastlane and new Interstate battery. Difficult to start in the morning under 40 degrees F. Cranks fine, but won't fire. Starts after the 3rd attempt at cranking and with a little throttle. Starts fine the rest of the day. Could the problem be with an air or a water temperature sensor? Can this be checked with a volt meter?

Mark