986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post - P0430 Code

lkchris · 05-25-2015, 02:18 PM

The CAT "expects" (by design) an exhaust gas mixture that it can successfully clean up. If it doesn't get it the output from the cat won't be clean, obviously. In many instances the reason the cat doesn't get what it wants is a malfunctioning MAF. It all starts at the MAF and a "bad CAT" code may be the result but not the cause.

IMHO the weak link in the system is most often the MAF. CATs are required by law to last for 8 years/80k miles or else it's a free warranty replacement. 986 original cats are all past warranty of course, but the point is they are pretty tough designs.

I'm not positive, but I expect the only thing that will generate a bad MAF code is an electrical fault in the MAF itself. If it's just not creating a proper mixture that can be burned efficiently, expect codes most often for downstream components. But look at the MAF first. And, I'd expect the success rate for just "cleaning" the MAF to be small.

Discussion?

05-25-2015, 02:18 PM	#17
lkchris Registered User Join Date: Jan 2014 Location: Albuquerque, NM, USA Posts: 730	The CAT "expects" (by design) an exhaust gas mixture that it can successfully clean up. If it doesn't get it the output from the cat won't be clean, obviously. In many instances the reason the cat doesn't get what it wants is a malfunctioning MAF. It all starts at the MAF and a "bad CAT" code may be the result but not the cause. IMHO the weak link in the system is most often the MAF. CATs are required by law to last for 8 years/80k miles or else it's a free warranty replacement. 986 original cats are all past warranty of course, but the point is they are pretty tough designs. I'm not positive, but I expect the only thing that will generate a bad MAF code is an electrical fault in the MAF itself. If it's just not creating a proper mixture that can be burned efficiently, expect codes most often for downstream components. But look at the MAF first. And, I'd expect the success rate for just "cleaning" the MAF to be small. Discussion? __________________ Kent Christensen Albuquerque 2001 Boxster 2007 GL320 CDI, 2010 CL550 2 BMW motorcycles Last edited by lkchris; 05-25-2015 at 02:23 PM.