jleetkd

I believe my catalytic converter is going bad and the exhaust is coming out a little bit too rich causing the rear 0xygen sensor to trip the SES light to stay on all the time. Since I don't have any emissions law where I live, I am not going replace the converters any time soon.

Therefore, is there an after market sensor that I can use to replace my rear oxygen sensor so it will always return a good code and turn off my SES light? I prefer not to disable my SES light because if it comes back on, I know I could have another problem.

Thanks in advance.

IceY2K1

iTrader: (3)

How many miles do you have?

Get the TSB performed by the dealer. They'll reflash the ECU and probably put in a new 02 sensor(s) depending on if you're Fed or Cali spec.

The cats don't go bad UNLESS there is something major going on.

Print this out and go to the dealer:
http://maxima.theowensfamily.com/tsb/ntb02-051a.pdf

jleetkd

I forgot to add what I have.

I have a 2000 Maxima GXE with almost 43k on it. The car has a salvage title on it. It was involved in a flood at a dealership in New Jersey and the water was high enough to get the carpet in the car wet. That is why I figure the cats went bad......

Thanks for the link, I will check it out......

IceY2K1

iTrader: (3)

Pay them to perform the TSB and it should fix everything.

Doubt it's the precats even with the water damage.

jleetkd

Thank you. It is greatly appreciated!

IceY2K1

iTrader: (3)

I'd recommend you go to your local auto parts store to get the code pulled for FREE first, just incase.

jleetkd

I had that done already when I took it to my mechanic last week, free of charge and the code indicated it was the rear 02 sensor.

I am going to take your recommendation regarding the TSB and bring it to the dealership.

IceY2K1

iTrader: (3)

Cool...let me know how it turns out and what they try and charge you.

I'd pay the 1/2hr for the ECM reflash and do the 02 myself.

jleetkd

Well, I just got my 2000 Maxima back from the dealership yesterday and it turned out to be the inevitable inigition coils problem. The mechanic I went before I went to the dealership said the coils were fine but that was not the case because when I drove, I notice a rattling sound coming from the engine, like take a bunch of BBs and shaking it in a tin can. The rattling noise was due to the coils misfiring. I had one coil almost gone and several others that were on their way.

I spoke with the mechanic directly and he said due to the misfire, the engine was not getting a fuel detonation and since the fuel was not being burned completely would enter the cats causing the rear 02 sensor to go off. When he read the ECU, he got misfire codes as well as the rear 02 sensor, something the previous mechanic neglected to tell me. The past two time, when I had the ECU reset, the SES light would come on within 20-30 miles of driving. I already have driven close to 50 miles already and the SES light has not come on.

All in all, this time so far, the dealership has been good to me except for the $632.00 I had to shell out for the ignition coils, parts and labor.....

jleetkd

"the engine was not getting a fuel detonation"

I meant "the engine was not getting a COMPLETE detonation" Sorry....

MaScott

Hmm... I seem to remember I read in the Haynes Maxima2000 repair manual that the rear O2 sensor does not affect the BCM...

jleetkd

What does BCM stand for if you don't mind me asking?

MaScott

BCM is the Body Control Module, a half of your onboard computer that controls the way all of the car's subsystems are running.
The other half is called ECM (Electronic Control Module), which, as far as I comprehend, stores all the settings and programs and compares the pre-set parameters against the readings BCM provides to it, throws a flag if some parameter is out of range.
That's the way I understood it.

IceY2K1

iTrader: (3)

Never heard nor seen of a "BCM" in the FSM.

Also, the rear 02s will signal precat failure(Cali spec) or main cat failure(Fed spec), but are not used for fuel calculations under normal conditions.

Glad to hear the problem was diagnosed and that does make sense.