O2 sensors -- how many are there?

[SF944]

O2 sensors -- how many are there?

OK, so I got this check engine light last season then read the code as a "Rear Heated O2 sensor."

Somehow I came up with the assumption that the NSX has 4 oxygen sensors, two on the front bank and two on the rear. Maybe it came to me in a dream, I don't know.

The car's been hibernating for the winter, but I happened to be at an Acura dealer today, so I checked for a price. They tell me there are only TWO O2 sensors, 1 front and 1 rear.

What's the definitive answer?

Also, the dealership wanted $246.71 for the part, and 2 hours labor to put it in. I'm thinking that as long as I can get to it, it is probably a DIY install, right?

Any advice on where to get the part at the best price and how to go about swapping it in?

 

[Tantheman]

2 for each of the catalytic converter..

Tan

 

[Bart Geerts]

Indeed 2 O2 sensors. I know it's confusing, because normally when people talk about front and rear sensors they mean 1 in front of the cat and one behind the cat. On the NSX it means 1 for the front row of cilinders, 1 for the back row, both in front of their respective cat.
As for D.I.Y. I bought an O2 sensor from Honda, don't get tricked into buying a cheaper BOSH part or some other make, the internal resistance of the heated part isn't the same.
I hope you have better luck than me, I just can't get the sensor out; and have to take the exhaust of the car to get good grip on the sensor. (the sensor is difficult to reach, and when you reach it not much space to get a lot of force on it)
I hope this makes any sense to you and will be of any help....

 

[Larry Bastanza]

Gents,

The FIRST question is WHAT YEAR car?? 1991-1994 have two, 1995 and up have four(OBDII),

If you are OK with a soldering iron you can get very good deals on "generic" sensors(search the web). Specific application sensors usually have matched wire length and connectors. So you can use the old wires and solder them onto the new sensor. Also if you are an NSXCA member you can get at least 25% off for an OEM sensor.

Before that though you need to find out if the sensor is really bad. Take a look at the procedure in the on line manual (page 11-32). For this issue you just need to get an ohm meter and measure the resistance of the heater, so you measure across two pins of the 02 sensor connector.

If it is bad, you will need to get a 02 sensor wrench ($10 at Autozone), and remember NO liquid wrench, WD40, etc. Removal and installation dry.

HTH,
LarryB