One problem related to emission control has been reported for the 2004 Chevrolet Trailblazer. The most recently reported issues are listed below.
The consumer had the sensor code p0171 replaced on the 2004 Chevrolet Trailblazer but the check engine light still illuminates on the dashboard. The consumer also felt a loss of power and the vehicle would not accelerate properly. Bucking and hesitation was current as well. The consumer was told an oxygen sensor was needed.