I have a 2001 Mazda MPV with 90K miles. It has been diagnosed with codes P0421, P0431, and P0051 which I am told requires replacing the catalytic converters and the O2 sensors at a cost of $2450.00. The van has been serviced as required by the mfg.

Does anyone know if this cost is a reasonable estimate in the piedmont area of North Carolina? Also, are there aftermarket converters that will work without modification that may reduce the cost of the parts? And finally, at 90K miles, is it reasonable to think that I can get another 90K miles without spending a chunk of $$ in this van assuming that I continue to have it serviced as required; i.e, are there any known major mechanical issues for this vehicle? Thanks,
Phil

 

There are aftermarket converters for the van, Quite a bit cheaper but OEM are the best quality. I can understand if it needs converters or o2 sensors but not both. I would get a second opinion i think. A code for cat efficiency is set by comparing the o2 in front of a converter and one after a converter so the o2 is apparently working so i see no need to replace the o2 sensors. If it needs all that then it will need a lot more really because something destroyed them. I think they are going too far and covering their butts.