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How to cure Cel/Mil from removing cat with Non-Fouler

2001 mpv
Thanks for the reply.

I got a quote from the dealer who said that 0431 code was for the cat and they want 1700 + tax. I'm tempted to try the non fouler idea but I'm concerned that the inspector will be a jobsworth and go over everything and spot it.


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Mazda Protege ES 2003
Could soneone clarify this for me. This is an obx header. It has 3 openings but the car has only 2 bungs..?
What are those for? (1-2-3) and what do i connect on which?

2002 Mazda Protege ES
1. is for the egr pipe that goes to the intake manifold, 2. is for the upstream o2 sensor, and 3. is for the downstream one. The downstream is the one for the non-fouler.
02 protege5
dammit i just order another 02 sensor cuz of the CEL . If i would have known about this when i installed my header last week i could have saved 100 bucks..Oh well i guess i/ll use the new 02 when it gets here and do it then
2001 mazda protege mp3
Has anyone had issues with o2 sensors runing these? I've been through 3 in the past few weeks, I'm waiting for auto zone to reject my warranty.
2003 mazdaspeed protege
ive just tried this idea and did not work for me. i have the corksport exhaust with no cat so i thought id try to get rid of the cel. did exactly what the tread said and i screwed it into the bung on the stock jpipe and did not work for me. any ideas what else i could do??
2003 Mazda Protege 5
Here's another point to make.Aren't these fancy computers supposed to be able to be reprogrammed for engine changes,like exhaust flow,air/fuel ratios,etc......

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