I gotta get at least another year out of my 2004 MPV -my MA inspection is due this month & I am throwing a P0431. We have fought with CEL's since just after 80K...we are at 130k now. I have replaced O2 sensors every year, but I think the cat is finally shot now and I want to try the anti-fouler trick. Exactly which O2 sensors do I need to do this with? I am tired of replacing coils and o2 sensors...it runs fine.