Ok well thanks for all the support and positive comments
J/K.
Well it wasn't that bad of a job actually. Hardest part turned out to be how to get the Oxygen sensor connector off of the clip it was attached to. Magnitudes easier than when I had to change it on my Accord. Anyway here's a little DIY FYI on replacing the rear oxygen sensor with a generic sensor.
Time - 2 hours over 2 days.
Total Time - 2 hours over 2 days
Difficulty - 2 only because your original Oxygen sensor might be difficult to work loose.
First-Time Cost - $50
People - 1
Interval The factory recommended service interval for this procedure - NA
Standard Tools - Socket wrench, 12mm socket, 4" extension, 22mm wrench, 1 other wrench near 22mm, good penetrating oil.
Special Tools - None
Service Manual - Couldn't find it.
Notes - I would normally let the dealer do this work and would use an OEM oxygen sensor, but because of the dealer being out of stock and time constraints I temporarily used a universal O2 sensor. I used an NGK (NTK) part #21027. The autoparts stores that I tried didn't have anything listed for the NSX, but according to NOPI, the PN for the 94 Accord EX (vtec engine) is the same as for the 94 NSX.
First you need to get the car up on jack stands. Follow all the safety precautions while doing this of course. Also, make sure to do this on an absolutely cold engine, your forearms will be pressed against the cats most of the time so make sure the car is completely cooled down before you start. The only item that needs to be removed to access the sensor is a piece of heat shielding. 3 12mm bolts hold the shielding on. 2 are adjacent to the O2 sensor and the 3rd is towards the passenger side. Its a little difficult to maneuver the socket wrench to get to them, but its not very bad, just takes a little patience to get the best angle. Sometimes its easier from beneath the car and sometimes its easier from the engine hatch. After the 3 bolts are out, you can push the shielding out of the way. As soon as possible spray penetrating oil on the oxygen sensor and let is sit over night. I use PB blaster, its the best stuff I've found for loosening rusty bolts. The next day cut the wires coming out of the O2 sensor near the sensor so you can get the closed end of the 22mm wrench around the sensor. After you get the 22mm wrench on it I suggest connecting another wrench about the same size to the 22mm wrench to lengthen the moment arm. Even though penetrating oil was used it will probably take a good bit of force to loosen it. That's about it. The only other thing is removing the electrical connector for the sensor. To remove the connector you need to be under the car and feel for a little tab to pull up, then the connector will slide towards the ground off of the hook it is mounted to. One last note I couldn't find the wiring diagram in the manual so I had to figure them out for myself. On the OEM sensor the 2 black wires were for the sensor heater, the white wire is the signal wire and the green wire is the ground. On the NTK sensor the white wires are for the heater, the black wire is the signal wire, and the grey wire was the ground. Installation is the reverse of removal.
Cheers
-Mike
Edited for spelling
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1994 Red/Black NSX #418
Forums Nazi Groupie
[This message has been edited by hendu (edited 24 June 2002).]
[This message has been edited by hendu (edited 24 June 2002).]
