Car has just 100,000 miles. O2 sensor has never been changed - and MIL code indicates the need to do so now. Are there any precautions re cracking the old one loose? I could buck off the wires and use a conventional 6 pt socket, after thoroughly dosing it with good penetrating oil,.possibly heating it a bit with a reg. propane torch (?), leaving for a few days / dosing it, etc. This long left in place are they ever reluctant to come out?
Suggestions re Changing Upstream O2 Sensor - '97 Civic EX
- Thread starter Cdn17Sport6MT
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Can you get an end wrench on it? I would save cutting the wires for last , in case you can't get it out. If you have a stout airgun and can get it to the sensor, then cut the wires , otherwise leave the option of driving it to the muffler shop.
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A propane torch and o2 sensor socket will do it (preferably the one that is open-ended and offset, not the long cylindrical one). Look for an o2 sensor with the smallest gap possible to avoid it splitting and rounding things out, with a propane or MAPP torch it is going to come out just fine.
I've removed tons of super crusty ones that had never been removed since the car was purchased and have been around the mileage you posted or more, this is in NY too which is probably as salty as where you are. It's easier getting the o2 sensor out than it is to disassemble the exhaust. They're big enough in diameter to where you can use a breaker bar or a long ratchet.
Propane torch it, o2 sensor socket with a breaker bar or long ratchet will do it. Even a long box-end will do it.
I've removed tons of super crusty ones that had never been removed since the car was purchased and have been around the mileage you posted or more, this is in NY too which is probably as salty as where you are. It's easier getting the o2 sensor out than it is to disassemble the exhaust. They're big enough in diameter to where you can use a breaker bar or a long ratchet.
Propane torch it, o2 sensor socket with a breaker bar or long ratchet will do it. Even a long box-end will do it.
Originally Posted by spasm3
Can you get an end wrench on it? I would save cutting the wires for last , in case you can't get it out. If you have a stout airgun and can get it to the sensor, then cut the wires , otherwise leave the option of driving it to the muffler shop.
I will check tomorrow re end access. Gd suggestion re NOT cutting off wires (as a safeguard). Thx!
Can you get an end wrench on it? I would save cutting the wires for last , in case you can't get it out. If you have a stout airgun and can get it to the sensor, then cut the wires , otherwise leave the option of driving it to the muffler shop.
I will check tomorrow re end access. Gd suggestion re NOT cutting off wires (as a safeguard). Thx!
Originally Posted by spasm3
Can you get an end wrench on it? I would save cutting the wires for last , in case you can't get it out. If you have a stout airgun and can get it to the sensor, then cut the wires , otherwise leave the option of driving it to the muffler shop.
I will check tomorrow re end access. Gd suggestion re NOT cutting off wires (as a safeguard). Thx!
Can you get an end wrench on it? I would save cutting the wires for last , in case you can't get it out. If you have a stout airgun and can get it to the sensor, then cut the wires , otherwise leave the option of driving it to the muffler shop.
I will check tomorrow re end access. Gd suggestion re NOT cutting off wires (as a safeguard). Thx!
Originally Posted by NoNameJoe
A propane torch and o2 sensor socket will do it (preferably the one that is open-ended and offset, not the long cylindrical one). Look for an o2 sensor with the smallest gap possible to avoid it splitting and rounding things out, with a propane or MAPP torch it is going to come out just fine.
Thx for suggestion. I have seen some very husky open end (but small-gap) crow-foot wrenches that can be used with a breaker bar and possibly a short, short extension (if nec.).
I have to meas. the hex size.
Thx!
A propane torch and o2 sensor socket will do it (preferably the one that is open-ended and offset, not the long cylindrical one). Look for an o2 sensor with the smallest gap possible to avoid it splitting and rounding things out, with a propane or MAPP torch it is going to come out just fine.
Thx for suggestion. I have seen some very husky open end (but small-gap) crow-foot wrenches that can be used with a breaker bar and possibly a short, short extension (if nec.).
I have to meas. the hex size.
Thx!
Here's what I mean about good vs bad o2 sensor socket.
This one is "bad":
https://www.harborfreight.com/78-in-oxygen-sensor-socket-63702.html
This one is "good", notice the smaller gap, under high force the two halves will move away from each other (the metal bends), the smaller the gap the closer you are to the full strength of a normal socket without the cutout.
https://www.amazon.com/TEKTON-4929-8-Inch-Oxygen-Sensor/dp/B000NPUKIE
I have the Tekton as a cylindrical style o2 sensor socket, then I have this for the offset, open-end style.
https://www.harborfreight.com/3-8-eighth-inch-offset-oxygen-sensor-wrench-97177.html
If you're torching it's going to lessen the amount of force you have to apply so either of the two last ones should work. The cylindrical style has an advantage in that it doesn't change torque specs if you're using a torque wrench. The offset one will require you to treat it like a crowsfoot extension when it comes to torque specs.
This one is "bad":
https://www.harborfreight.com/78-in-oxygen-sensor-socket-63702.html
This one is "good", notice the smaller gap, under high force the two halves will move away from each other (the metal bends), the smaller the gap the closer you are to the full strength of a normal socket without the cutout.
https://www.amazon.com/TEKTON-4929-8-Inch-Oxygen-Sensor/dp/B000NPUKIE
I have the Tekton as a cylindrical style o2 sensor socket, then I have this for the offset, open-end style.
https://www.harborfreight.com/3-8-eighth-inch-offset-oxygen-sensor-wrench-97177.html
If you're torching it's going to lessen the amount of force you have to apply so either of the two last ones should work. The cylindrical style has an advantage in that it doesn't change torque specs if you're using a torque wrench. The offset one will require you to treat it like a crowsfoot extension when it comes to torque specs.
try to get it loose without heat if you can.
I've gotten them out with heat and without heat.
and sometimes with heat applied the threads strip out partially.
I've been able to put new ones in with the threads messed up but they turn in hard the whole way.
the ones I've been able to get loose with no heat, usually turn right out after the initial loosening and then the new one threads right in.
I've gotten them out with heat and without heat.
and sometimes with heat applied the threads strip out partially.
I've been able to put new ones in with the threads messed up but they turn in hard the whole way.
the ones I've been able to get loose with no heat, usually turn right out after the initial loosening and then the new one threads right in.
The trick to O2 sensors is impact. Give your breaker bar or wrench a sharp rap with a brass hammer to break it loose. Tugging and bending is what rounds them off or strips them out.
Unless you live in the rust belt it should come off without much grief. Put a proper tool on it. The downstream GM one I just took off with an open ended wrench with little effort. They anti seize them at the factory. Try it first, it may come off easy.
Many thx to all who have replied. Your kind help is apreciated ☺.
Many thx to all who have replied. Your kind help is apreciated ☺.
This is an up stream sensor ?
Thought I had ( if it is fairly accessible ) is drive the car far enough to get it HOT .
Park it and give it a good squirt of PB Blaster . Might do this several times .
Is the wire " hard wired " or can you unplug it ? If you can , unplug it . Then can you get to it with a box end wrench ? If not , buy the appropriate O2 socket .
Best of luck to you ,
Thought I had ( if it is fairly accessible ) is drive the car far enough to get it HOT .
Park it and give it a good squirt of PB Blaster . Might do this several times .
Is the wire " hard wired " or can you unplug it ? If you can , unplug it . Then can you get to it with a box end wrench ? If not , buy the appropriate O2 socket .
Best of luck to you ,
Originally Posted by WyrTwister
This is an up stream sensor ?
Thought I had ( if it is fairly accessible ) is drive the car far enough to get it HOT .
Park it and give it a good squirt of PB Blaster . Might do this several times .
Is the wire " hard wired " or can you unplug it ? If you can , unplug it . Then can you get to it with a box end wrench ? If not , buy the appropriate O2 socket .
Best of luck to you ,
Time is your friend when using the penetrant. Plan for 24 hours and like above, several blasts spaced across the day.
This is an up stream sensor ?
Thought I had ( if it is fairly accessible ) is drive the car far enough to get it HOT .
Park it and give it a good squirt of PB Blaster . Might do this several times .
Is the wire " hard wired " or can you unplug it ? If you can , unplug it . Then can you get to it with a box end wrench ? If not , buy the appropriate O2 socket .
Best of luck to you ,
Time is your friend when using the penetrant. Plan for 24 hours and like above, several blasts spaced across the day.
Beware the O2 sensor wrenches. Some sensors (Chrysler) are very sensitive about it not being a "22mm or 7/8" wrench, and quite specifically need either spec. Ran into enough Chrysler ones that were jiggly under just about any O2 wrench, but a good open 7/8" wrench was like bank vault parts coming together.
If they feel nasty, I like to give them several small doses of CRC Knock'er Loose. It's proven to be a superior penetrating lube above all others. Pricey, but I've gotten loose things that I had no right in the universe to get loose simply by using that stuff.
If they feel nasty, I like to give them several small doses of CRC Knock'er Loose. It's proven to be a superior penetrating lube above all others. Pricey, but I've gotten loose things that I had no right in the universe to get loose simply by using that stuff.
New CRC product (new to me). Thx!
I just replaced the upstream sensor in my 04 civic. I tried to use some loaner sockets from autozone and advance but couldn't get it out because the deep socket and crows foot socket were a little big for the tight space and weird angle.
I didn't want to cut the wires so I disassembled the plastic connector at the end of the wires and then used a box end wrench to get it out. The connector wasn't too hard to take apart and using a 6 point wrench and tapping it with a mallet made it come loose easily.
I didn't want to cut the wires so I disassembled the plastic connector at the end of the wires and then used a box end wrench to get it out. The connector wasn't too hard to take apart and using a 6 point wrench and tapping it with a mallet made it come loose easily.
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