p0421 code among others

brett02

Member
Hey guys, new here but I have had my P5 for 3 years now. In the last month I have had all sorts of problems.
1) mass air & fuel pump go out
2) 2 weeks later coils, wires, plugs and warm up cat go bad
I had everything replaced except the catalytic converter, Mazda wanted too much.
The car has 85k on it so the 8/80k doesn't cover it and neither does the extended warranty.
I looked in the search function on this particular forum and had seen that gutting the catalytic converter and using a spark plug non-fouler would fix this as well as give my P5 some better performance, which wouldn't be a bad thing since it is an automatic. I also had noticed a website that sold these catalytic converters at a little more than half of what Mazda wanted, nice.
My question is do you think gutting the cat and using the spark plug non-fouler would void my extended warranty or do you think that I would be just fine.

Thanks

Brett
 
Hey guys I had to have this thread moved as I dumbly put it in the welcome forum (doh)

I would appreciate any feedback you guys could give me.

Thanks for your help aMaff!
 
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