2005 Buick La Crosse 6 cyl Two Wheel Drive Automatic 43600 miles
The check engine light comes on with P0420 code. Regular system diagnostic test shows engine running clean. Freeze frame shows code being set only at idle, at 15 minutes and again at approximately 45 minutes. What is the cause and what is the fix?
Wednesday, September 1st, 2010 AT 5:51 PM