One problem related to emission control has been reported for the 1999 Ford Ranger. The most recently reported issues are listed below.
Engine check light(po455 code) came on 5 times since new, problem in fuel system and no vacumn being able to be detected by the onboard computer system in fuel system (leaking vapors?), problem not corrected to date, attempting to track down problem (fuel tank changed, canister purge valve changed, problem persists).