I have a Mazda 626.2001 4 cyl. Auto. 76K. Check engine light came on. Autozone checked and code P0421 came on. The counter guy suggested a tune-up. I had one in March. Maybe 5K on car since then. The read out states warm-up catalyst efficiency for bank 1 is below threshold. What does that mean and where do I go from here? Thanks
Bill from ohio
have the same problem?
Friday, October 20th, 2006 AT 11:14 AM