One problem related to gas recirculation valve (egr valve) has been reported for the 2003 Ford Explorer. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2003 Ford Explorer based on all problems reported for the 2003 Explorer.
About 3 months ago, my Explorer began occasionally experienced dramatic, random engine acceleration. While driving, the rpms would shoot up for no apparent reason. 2 months ago, it was taken to the Ford dealership in millington, TN. They found no problems and hinted it was "driver error". A week later, I made an 800 mile drive to visit my newly hospitilized father. The sudden, drastic increase in rpm' started out happening 1 - 2 times in the first 30 minutes. The frequency rapidly increased, and 4 hours into the trip, the sudden acceleration was occurring at least 1 time every 5 minutes or so. After arriving in pittsburgh, the Explorer was again taken to a Ford dealership. They informed me that the co2 detector had gone bad. This was covered under warranty, but since I was driving with a bad detector, the egr sensor was caused to malfunction. I was informed that this was not covered under the warranty since it was a result of my continuing to drive it with a bad co2 detector. The egr sensor cost me $300 to get replaced. A week after this "repair" was made, I began the trip back to TN. 2 hours into the trip, the sudden, drastic accleration started again, and soon was occuring several times every 30 minutes. On reaching TN. , I once again took the Explorer to the Ford dealership in millington. They were unable to find any problem. So, not only did I pay for a repair that 1) was caused by the dealership's inability to find a problem, it 2) should have been covered under the warranty. Then it became apparent that the "repair" did not even fix the problem. To this day, the random acceleration is a problem.