2003 Cadillac Escalade Ext V8 All Wheel Drive Automatic 110000 miles
I recently purchased a 2003 Cad Escalade Ext with 110,000 miles that runs and looks terrific. The vehicle has been maintained well.
The previous owner has upgraded the exhaust system with performance muffler with dual pipes. My check engine light came on recently and I had the code checked to reveal that both catalytic converters were malfunctioning. The mechanic said that this was unlikely so he cleared the code. I drove it for about 350 miles over a 3-day period then the check engine light came back on. I took it in for a emission test to determined if the cats were doing what they are suppose to do and I passed the test with flying colors HC limit 150 reading 10 CO limit.07 reading.05. This test was done with the check engine light on. My question: what is causing the check engine and why did the problem not show up in the test? Any help would be appreciated. Thanks.
Friday, May 15th, 2009 AT 10:57 AM