One problem related to emission control has been reported for the 2001 Nissan Frontier. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2001 Nissan Frontier based on all problems reported for the 2001 Frontier.
2/25/05 I purchased a used Nissan froniter SC '01. One week later the "service engine" light appeared. A Nissan technician diagnosed the problem as the oxygen sensors not providing feedback due to condensation in the wire harnesses. The tech. Told me that there was a bulletin he found stating that the wire harnesses in that year Frontier were found to be faulty and replaced with updated harnesses, which I would have to buy along with four sensors, to fix my problem. The cost in parts was $965 and labor is estimated at $880. Nissan will not even pay for partial parts even though they admit it is faulty product. I have contacted them to complain with the appropriate department and now they will not return my calls.