(duplicate post in C5 tech - I posted here because there are more scan and tune types here)
I put a low-mileage 2003 Z06 H-pipe on my 02 vert, mated to a Z06 ti muffler system. Other than that, all stock at about 12,000 miles.
Last night it threw a CEL with P0430 code for the second time in about 6-7 weeks. A bummer to be sure.
I'm just wondering if there's any thing that can set this code besides the cats? So far it's been 0430 both times. Maybe the rear o2 sensor on that bank (right I think, got to look up the code again to be sure)?
Otherwise I may need to put the 4-cat h-pipe back on.
Could be a bad O2 sensor although my bet is the cat on that side is bad. What's your gas mileage been like and do you have any accessive black soot in the exhaust on that side? A bad O2 will have those signs. Since you just did the H pipe make sure of your connections and whatnot to that sensor too. My bet would be the cat though. Do you have a-tap or efilive where you can look at the mv's to the O2's??? That will tell you if the sensor is bad too. Good luck.
Thanks for the info. I don't have autotap or efi, so I'm shooting blind. I'm hoping it might be a marginal sensor. Maybe they got some anti-sieze or grease on it when transfering it from the original h-pipe. I took a good look around underneath the car, traced out the wiring and made sure the O2's were plugged in and tight. Of course, they were. I noticed the shop used some kind of high-temp orange stuff on the flange to the mufflers. Normally, the factory gasket goes on dry between the mufflers and pipes. Could be some silicone poisoning? I dunno, probably wishful thinking on my part.
Took my handy IR pyrometer and found both cats to be running identical temperatures, which might be taken as a good sign. No sign of soot or fuel smells.
I just had our 2000 start throwing the same code on the PS side..........all is tight and its an FLP sytem with their hi-flow cats..........only 12K miles on them. Cats are also the same temps! I think rear O2 sensor.........of course I told, Julie my wife I can fix it by putting in the straight pipes, and O2 sims......
Corvette Store
Z06 H-pipe and code P0430
