2000 sentra 1.8 0420 0430

[gwoods]

I am working on a 2000 Sentra 1.8 5spd manual trans car with 208,000k miles on it.

It runs great never had a blown head gasket.

The check engine light is on with codes 0420 and 0430.

Do you guys think it is the catalytic convertor or o2 sensors?

[nametakennow]

Pretty easy to pop off the exhaust and take a look at the cat. Tougher to diagnose the sensors.

[gwoods]

Thanks for the vote and reply.

I am pretty sure it is the cat. I talked with a tech at one of the Nissan dealers in town and he said the manifold cats don't last much past 150k miles.

Good news is I found a wrecking yard that will sell me the 4 O2 sensor and manifold cat set up from a wrecked 2001 Sentra with 80 k miles for $125.

That should fix the problem for a while either way

[nametakennow]

Yeah, at that mileage, it can't hurt to replace the whole shibang anyway.

[ABNRML4U]

Yeah! Junkyards for the win. LOL!

[LMAOuse!]

yay sentra!!

[gwoods]

UPDATE

replaced the O2 sensors and exhaust manifold. The crank and camshaft position sensors both immediately failed.

But most importantly the 0420 and 0430 codes are gone. The car went through emissions and passed.

The car now overheats for no apparent reason sometimes. The Efans both come on with the AC but methinks the sensor that tells them to come on with coolant temp has failed.