My auto technician read the subject code for my "check engine" light as BANK 1 CAT EFFICIENCY BELOW LIMIT. His diagnostic tool listed 8 or 9 possible causes. I recently bought this car (98 Silver Frost SVT) with 110,000 miles on it, and the check engine light came on after about 500 miles of driving. The tech reset it and said to come back if it comes on again and he would spend more time (and $$) troubleshooting. It came on again today, after about another 500 miles. I queried the previous owner who said he replaced "both" (?) oxygen sensors in the last 6 months. Any idea what the REAL PROBLEM might be? The car runs GREAT!!!! (No problems except for the stupid light).
