Pre-Cat being supposedly hollowed out?

[sexy6eclipse]

So here is the dilemma. About 2 years ago we took the high flow cat and resonator off and just test piped it. Had no problems til about a year ago. All of a sudden my exhaust blew apart (honeycomb coming through it) and we had the same exhaust on our other eclipse for a lot longer and never had a problem. All of a sudden my check engine light came on. Took it mitsubishi under warranty not knowing what was wrong with it. They told us the error codes were coming up at P0421 and P0431 aka the precats. The dealership then told us that the cats had been HOLLOWED out and wasnt covered under warranty. The car ran fine and we just continued to drive it. Well now its due for DEQ emissions test here in oregon. So we pull the precat off and were looking at them and cant find ANY evidence of it being hollowed out granted the honeycomb is not present. Could it have blown out? Does anyone know if the honeycomb is a pressure fit or welded? We have taken it to several muffler shops and they are saying that it hasnt been hollowed out, that more than likely it blew out. Now its a battle with mitsubishi fixing the car and proving that it was defective. Anyone with insight to this is greatly appreciated.

[SMeclipseGT]

get headers lol

[joeyb]

you could threaten them with court, say you have several technitians lined up to testify that it was not hollowed out...but that's gonna be time, $, and pain. Just buy some RRE headers and cut your loses.

[Clovisman]

Not sure what you are saying. On this car you are talking about, does it also have a tester pipe, or does it still have the secondary Cat installed?? If the honeycomb from the pre-cats broke-up, then the secondary cat would have collected that materal causing the secondary cat to plug, go bad, and stall the engine. That's what happens when a cat melts down or gets clogged, you engine performance suffers baddly, or the engine will stall because of the back pressure.

So if this is a used car, then the owner before you removed the honeycomb from the pre-cats, and to prevent any codes from being set, probably installed spacers on the rear O2 sensors to pull those sensors out of the exhaust stream and prevent any codes being set.

But yes, the honeycomb is welded into the cat, someone would have to spend some time to remove all evidence that there was a cat install, i.e. if someone removed it, there would be some trace or evidence that a cat was installed at some time. If it came factory install without cat material in the pre-cats, as soon as they started the car it would have thrown a code.

But bottom line, either you or the previous owner is responsible for the repairs.