Cel Code Problems... Checked Everything

[Siege911]

Okay, so I got a PO420 code the other day... checked both o2 sensors, they're fine, and I don't know how to check the catalytic converter, but I didn't think that they just went bad. Anyways, I've seen them for like $1000, and I definitely don't wanna buy a new one. Any ideas on what else could happen, and what "P0420 Catalyst System Efficiency Below Threshold" means? Thanks.

[dubcac]

It means the cat isn't functioning up to par, or one of your O2 sensors is getting a reading it shouldn't be getting. The cat could be bad, either poisoned or clogged, or the catalyst inside has been knocked loose. Take your cat off and shake it, if it rattles, the catalyst has been knocked loose. Also, hold one end up to a light, and look through it. If you can't see the light, it's clogged.

[simplegreen]

you can buy catco or carsound cat's online for like 30 bucks but you'll need to buy flanges to have a shop weld on along with a o2 bung for your o2 sensor to go total cost 35 bucks + shop cost (if you can't weld)

[Siege911]

cool, but if i go with one of those cats will the cel go off, or will it stay on still?

[Vtec_Power]

just food for thought.

I had a 1997 Del sol, and both pre-cat o2, post-cat o2 and the cat itself were fried. Apparently high mileage (180k) plus running really rich will do that. So it is possible to have shit crap out on you out of nowhere.

1000.00 for a cat.. is that a D16Y7?

*edit nvm.. just saw your sig.. its a D16Y8..not entirely sure about this but isnt your cat part of the exhaust manifold?

[Doughboy]

Originally posted by siege911@Jul 11 2005, 12:01 AM
cool, but if i go with one of those cats will the cel go off, or will it stay on still?

reset your ecu if it doesnt shut off after its installed. Shouldnt be an issue though.

[dubcac]

Originally posted by Vtec_Power@Jul 11 2005, 04:43 AM
just food for thought.

I had a 1997 Del sol, and both pre-cat o2, post-cat o2 and the cat itself were fried.* Apparently high mileage (180k) plus running really rich will do that. So it is possible to have shit crap out on you out of nowhere.

1000.00 for a cat.. is that a D16Y7?

*edit nvm.. just saw your sig.. its a D16Y8..not entirely sure about this but isnt your cat part of the exhaust manifold?

That didnt crap out from nowhere, it probably crapped out from the O2 sensors being bad, and then running extremely rich. That can kill a cat.