dozu

with emission inspection due soon and CEL on, I went to Autozone and they pulled P0430 (cat efficiency) and P0153 (O2 sensor CKT slow response bank 2 sensor 1)

does this sound like a sensor problem, or is the cat really dead? what is the best course of action here? replace the O2 sensor first and see what happens? or just replace the sensor and the cat together?

any advice is appreciated!

01 Maxima SE, 5sp.

nelledge

iTrader: (6)

Pull the sensor and check it out. It's easy enough. How many miles on it?

I would never replace a catalytic converter on a whim. Too expensive for guess work.

dozu

thanks... car has 172k miles.

nelledge

iTrader: (6)

Higher miles would allow it to be either, but I always shoot for the more likely culprit. Catalytic converters should last a long time if the engine is running properly. You'll probably see that the O2 sensor is pretty fouled and corroded when you pull it. I say start there.

lyns1113

What was the end result? I have the same problem and 3 mechanics all want to change the cats and sensors, all at once. $1400 plus
Engine has no systems of running poorly....

dozu

so I got an oxygen sensor and put it in.

had to disconnect the battery to clear the codes... then drove 150 miles, highway and local, then took the car to inspection, got a 'monitor not ready'.

How do I tell if the computer is ready, before I take the car to the inspection station again?

thanks!