P420 Code What should I do first?????

[jullissia]

I have a 2002 Toyota Camry with 185k miles. The check engine light is on with the code p420 for inefficiency with the cat. converter. The converter has already been changed once before. What I want to know is if I clean the MAF and the o2 sensor would that be the cause of the code. As well it has a rattling noise by the converter and I take it that it needs to be changed and the reason its bad is that the o2 sensors have never been changed. Any thoughts?????

[gdanaher]

Cleaning the MAF is something that likely needs to be done anyway but I doubt it will solve the problem. The error is likely being generated by the O2 sensor at the cat. Either the cat is toasted again and the sensor is right, or the sensor is old and needs to be replaced. Since the sensor is relatively inexpensive I would change it first if you are just tossing money at it. Again, since it hasn't been replaced before and is near its end of life it wouldn't hurt. If the problem clears then all is well for awhile. If not then you need a new cat, but you were guessing that anyway.

Just be aware that at this mileage the vehicle is near its EOL so be careful what you do here. Perhaps a junk yard cat this time. Try to avoid spending much because you aren't going to see the value. At this age, bad things start to happen.

In another thread, some schmuck just bought an old Camry with 166k miles and paid top dollar because it had been cleaned up. With mileage like that the thing becomes a money pit. Good luck with yours though--you have likely driven your money's worth out of it!!

[jullissia]

Well I just took to a shop and they said that nothing is wrong with converter.

[gdanaher]

So, what did they tell you WAS wrong with the car?? The idiot lights don't come just because it is the holiday season.

[jullissia]

It needed a new converter and fuel injector cleaned

[profuse007]

Sounds like a recommendation from an untrained idiot, aka UTI. I suggest looking around on the web about p0420 bc a lot of ppl replace their converter and nothing.

Originally Posted by jullissia

It needed a new converter and fuel injector cleaned

[DOHCammer]

Originally Posted by profuse007

Sounds like a recommendation from an untrained idiot, aka UTI. I suggest looking around on the web about p0420 bc a lot of ppl replace their converter and nothing.

We have never had a car come into the shop with a code P0420 that a correct catalytic converter didn't solve. I say correct converter because some people change the wrong converter on multiple converter systems and of course it doesn't help. Any converters past the last oxygen sensor are not monitored and will not put out a P0420 light.