My Mazda 6 2005 model exhausts is red hot and idling is going up and down with a bad noise

SOURCE: Bad catalytic converter(s) ???

let the car run for about 15 min look underneath if the cat is bad its should be glownin

SOURCE: Loud acceleration noise in my 2003 Mazda 6 2.0 auto

one thing to check is rear engine mounting i have had a stone wedged in one and it causes a nasty noise when accelerating

SOURCE: how many catalytic converters on a Mazda Mpv 2003

I disagree. I believe there is 2 cats on the 03 MPV. If you look under the car. The 2 pipes from the headers meet right before the muffler. There is 1 cat under the vehicle and another right off the header (looks like an old glass pack muffler).

SOURCE: My 2002 3.0L V6 Mazda Tribute is blowing out the

I have the exact same problem right now. It is possible that a misfire due to a faulty coil damaged the pre-cat and I found pieces of it clogged in the main converter. Unfortunately, to repair it right, I would suggest replacing all three converters as well as upgrading the coils to napa echlin coils.

SOURCE: I need to replace my mazda mpv catalytic

Ok the fastest way to solve weather it is the cats in the exhaust system is to take it too a exhaust specialist and ask them to do a exhaust pressure test. They should have all the pressure drop data there and can tell you if there is to much restriction in the exhaust, if there is to much chances are they will be the cats, usually the front one. Yep your dad is correct with his theory, but excessive overfuelling will also cause the cats to build up excess heat and start to melt, or fall apart. So get a good service when your able too, plugs/filters and oils. Yep your firing order is correct.

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