One problem related to emission control has been reported for the 2001 GMC Yukon. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2001 GMC Yukon based on all problems reported for the 2001 Yukon.
On three separate occasions my check engine light came on and all three times the sai (emissions) valves were rusted causing them to fail. The dealer told me since the valves are located directly under the exhaust the condensation falls onto the them causing them to rust. They also said there is no permanent fix for this.