12-16-14, 12:36 PM
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Oxygen Sensor (O2) Bank 1, Sensor 2 DIY
01-17-14, 10:53 PM
#91
I would say watch and follow the way the old washer comes off.
IMHO the smaller flat area (left in picture) faces the sensor and the larger flat area (right in picture) faces the exhaust. If you mount it the other way, you would create a lip between the exhaust and the gasket which can collect stuff over time .. that would set in corrosion. If you do it the way I suggest then everything would be streamlined. There is enough flat surface to prevent a leak in either position.
Lastly, it is important that you torque both nuts evenly .. 1/2 turn at a time. I dont have the spec handy.
Salim
IMHO the smaller flat area (left in picture) faces the sensor and the larger flat area (right in picture) faces the exhaust. If you mount it the other way, you would create a lip between the exhaust and the gasket which can collect stuff over time .. that would set in corrosion. If you do it the way I suggest then everything would be streamlined. There is enough flat surface to prevent a leak in either position.
Lastly, it is important that you torque both nuts evenly .. 1/2 turn at a time. I dont have the spec handy.
Salim
Thanks!I did find the torque specs from the diagram posted earlier, 14 ft/lbs. Good thing I have a nice torque wrench.
03-16-14, 02:54 PM
#93
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Can't remove sensor
I just replaced the "hard" sensor to access. I'm now replacing the "easy" access sensor right behind the radiator. For the life of me I can't get this out. I've tried a breaker bar. I've tried PB (rusty bolt loosening solvent.) I just now tried heating the manifold to bright red with a MAPP gas torch and I still can't budge this thing. I am trying to turn this counter clockwise. I am beginning to wonder if these are reverse threaded somehow? What could possibly have locked this thing in so hard?
03-19-14, 02:17 PM
#95
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update
Just thought I'd post an update. I've tried another 24 hours of PB and a breaker bar again. No go. I called the dealer I bought this from and they said heat will often do it but if not you have to replace the entire manifold. I guess I will try torching it again and this time just burn the rest of the tank on it.
03-19-14, 02:21 PM
#96
Pole Position
The first two times I had that sensor replaced at the dealer they had to replace the manifold too. At least that's what they told me. The third time I did it myself. I used PB Blaster and alternately loosened and tightened the sensor until it finally popped loose. Took about 24 hrs of soaking, waiting, wrenching, reapeat.
03-19-14, 02:25 PM
#97
03-20-14, 04:38 AM
#98
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I just replaced the "hard" sensor to access. I'm now replacing the "easy" access sensor right behind the radiator. For the life of me I can't get this out. I've tried a breaker bar. I've tried PB (rusty bolt loosening solvent.) I just now tried heating the manifold to bright red with a MAPP gas torch and I still can't budge this thing. I am trying to turn this counter clockwise. I am beginning to wonder if these are reverse threaded somehow? What could possibly have locked this thing in so hard?
03-25-14, 05:55 AM
#99
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Conclusion
Well I gave up and took it in to a mechanic. After looking at it, they said the manifold definitely needs to come out. After taking it out, they couldn't get the old sensor bolt out. They told me they didn't have a new manifold and would have to order one. Right before ordering one, the manager was apparently able to get it out, saving me a few hundred dollars that a new manifold would cost. So in the end, they only charged me for 4 hours of labor. (I already had a new sensor.) Pretty decent guys at the Japanese Auto Clinic on Lee Highway in Arlington, VA.
From the short drive back the car is running smoothly. I will add that although the car ran without that sensor, it started to get kind of rough. The mechanic said there were a bunch of P300/P302 check engine light (CEL) codes showing up which indicate misfirings in certain cylinders. I think that was because the ECU wasn't getting a lot of information missing a sensor. So while you can drive your car without a sensor, I wouldn't do it for very long.
From the short drive back the car is running smoothly. I will add that although the car ran without that sensor, it started to get kind of rough. The mechanic said there were a bunch of P300/P302 check engine light (CEL) codes showing up which indicate misfirings in certain cylinders. I think that was because the ECU wasn't getting a lot of information missing a sensor. So while you can drive your car without a sensor, I wouldn't do it for very long.
03-25-14, 03:24 PM
#100
How the heck can someone say that they can't get it out if the manifold is removed? It will either come out or destroy the threads and come out. Sounds like complete BS to me.
04-17-14, 07:38 PM
#101
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Great write up and pictures. I was able to replace the downstream sensor without removing the driver's seat by moving it all the way forward to reveal the "T" shaped slit in the carpet. I made one cut in the carpet about 2" long toward the firewall and one horizontal cut to connect to where the carpet is cut for the rear heat outlet. This gave me enough room to reach in and disconnect the sensor. The carpet laid back down after the install and you can't even tell it was cut. The only hard part on mine was scraping the old gasket residue from the flange. I could tell that the gasket goes with the side with the most metal toward the exhaust. Thanks for all the good information.
05-17-14, 08:38 PM
#103
05-18-14, 08:16 AM
#104
Great write up and pictures. I was able to replace the downstream sensor without removing the driver's seat by moving it all the way forward to reveal the "T" shaped slit in the carpet. I made one cut in the carpet about 2" long toward the firewall and one horizontal cut to connect to where the carpet is cut for the rear heat outlet. This gave me enough room to reach in and disconnect the sensor. The carpet laid back down after the install and you can't even tell it was cut. The only hard part on mine was scraping the old gasket residue from the flange. I could tell that the gasket goes with the side with the most metal toward the exhaust. Thanks for all the good information.
ETA:
Last edited by timmui; 05-18-14 at 08:50 AM.
05-19-14, 03:22 PM
#105
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I don't know what the "access cover" that they refer to is. Bank 1 sensor 2 on a RX300 is behind the cat and in front of the resonator which is under the driver's side and why the connection is under the driver's seat. Read the thread. It has good info and pics. The thread postings are accurate, I don't know about your service manual.
