What does this mean? Someone please help!
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2005 Acura TL Question: My engine check light came on and it said "Catalyst Threshold Efficiency Low."
Answer #1Greg's Orange Auto (13388 Answers) , Orange, CA - (714) 361-9386globalhelper January 03, 2013, 13:03Master
one of your catts is going bad did it say bank1 or 2 and per catt or post catt. it means you o2 sensors are not seeing enough difference between pre o2 and post 02 but u need to figure out if its an 02 issue or catt issue.rec seeing a mech that knows these cars for proper diag