1999 Pathfinder "Check Engine Soon" light came on

Probably an Oxygen sensor.

The light come on my '02 Pathfinder last month and it was a "Swirl Control Valve" (fortunately fixed under warranty).

You need to get the code out of it to see what it is. There is a procedure in the FSM to make it tap out the codes by flashing the light if you don't have an OBD-II scanner.

there are about 80 different things that can turn on the check engine light.

so your guess is as good as mine.

get the codes read

Emission control component, too many to diagnose without an OBDII reader.

Thanks for the info.

In my part of the USA Schucks will rent one, and Autozone will read it for you.

Louis--

In Massachusetts I use Autozone. They will read the code for free. Hoping to sell you parts!

Thanks. I stopped by Checkers Auto and they lend the OBDII Scanner out providing you put a deposit down. The clerk told me that since I have the car in the parking lot, I could use it providing I let him hold my License.

The error code that I got is: P153, which he told me was the passenger side rear Oxygen Sensor.

How much should I expect to pay to service this? Or is the unit accessible and can be done w/o taking it in.

Thanks.

Oops, I meant to say P158.

The last O2 sensor I paid for cost just under $200 installed. They're not cheap.

Next time I will check out Bosch for their replacement O2 sensors. I'm curious to see how long they'll last.

Arn't those expensive Nissan sensors in reality made by ND or NGK and available for a lot less money?

The rear passenger sensor looks easily accessible (no corrosion on it, and made by Bosch... thus it probably was replaced already). There's two sections of the 02 sensor that has fasteners; one on top of the tranny, and another that's more accessible. Anyway if I am replacing the whole 02 sensor assembly (connector to the sensor), couldn't I just cut the old one after removal and run the replacement along the same path? Will this get rid of the "check engine soon light" or do I still need to have the system re-set afterwards?

If anyone has any pointer with do's & don'ts when replacing the 02 sensor, I'd really appreciate it.

Good question. Maybe Nisstech knows...

Seems to me I read right here about other Nissan models and the sensor actually having the NGK trademark logo on it. I would guess it's NGK. Bosch isn't a logical choice and Nissan sure doesn't make any components.