O2 Sensor Changed, Check Engine Light Still on...? Will it go off? [Archive] - Drive Accord Honda Forums

: O2 Sensor Changed, Check Engine Light Still on...? Will it go off?


redbug2
02-04-2011, 04:37 AM
Hello,

My mothers 2004 Accord had its Check Engine Light come on. She tried the gas cap tightening and that did not work. I had her take it to Autozone and they read the code on the computer. O2 sensor. She bought the Bosch O2 sensor that I changed yesterday.

That was not as easy as I thought.. Jacked up the car and had to remove the pipe from manifold. Not enough room to get socket on 02 sensor. Removed bolts from the exhaust mount and dropped down the front end of entire exhaust. Kept exhaust propped up about 5 inches because Cat sensor was still wired in and at its length limit. Then, vise gripped the flange end while I turned the special socket to remove the O2 sensor. That's tough because of the flexible joint on the pipe, you need to anchor flange before loosening 02 sensor.

Anyway, 02 sensor is in. Drove the car about 25 miles and the light is still on.

Will the light eventually go off by itself? (If the O2 sensor was the problem and is now fixed?) Or, do I have to somehow reset the check engine light? Autozone did state that they would not turn off the light.

Thanks,

redbug2

mobiless2
02-04-2011, 04:58 AM
Have to get code cleared. I purchased a code reader from Autozone for $39.99 & cleared the code.

baracus
02-04-2011, 05:37 AM
Did you get the actual code or did the guy at Autozone just tell your mother which O2 sensor was needed? I ask because the downstream sensor on my Accord ('03 I4) went out last year and initially the guy told me that it was the upstream sensor. I double-checked based on the code when I got home and discovered that he was wrong. For me the CEL went off on its own after I changed the sensor.

chiggaraccord03
02-04-2011, 09:05 AM
Agree. Make sure you change the correct o2 sensor. Autozone informed the o2 downstream sensor was bad. Brought Bosch OEM o2, installed it and CEL went off after the first start.

nehonda
02-04-2011, 12:31 PM
Just because you get an O2 sensor code doesn't necessarily mean the sensor is bad. You can have a rich or lean fuel conditions, exhaust leaks, shorted wires and other things causing the sensor to turn on the engine light. There are several diffrent O2 sensor codes that will help isolate the cause. You really need to troubleshoot the cause of the problem before throwing parts at it.

NightMarcher01
02-04-2011, 05:11 PM
First of all. Are you I4 or V6?

Second... why didn't the dude tell you the code? How can he just say o2 sensor? If you're I4, there's 2. And if you're V6, I believe there's 3.

They have different duties. So by him not telling you the code, you might have just spent money on something that you didn't have to change.

You should talk to the Manager.

Anyway, try disconnecting the battery. Wait 10 minutes, and connect it again. That should restart the computer. If the CEL is still on, then you just wasted your money!

This happened to me about 3 weeks ago... I even made a thread about it. The code was P0134

mobiless2
02-04-2011, 07:32 PM
There is (4) O2 sensors on V6. 2 per side.

redbug2
02-05-2011, 03:13 AM
Its a 4 cylinder.

My mother took the car to Autozone on my recomendation. I would hope that the guy reading the code would be smart enough to sell her the right sensor...(wishfull thinking),,,, Is the Cat sensor the same? If so, would be nice if I could swap the old front sensor provided the front one was good... Or, maybe they are both bad?

NightMarcher01
02-05-2011, 03:45 AM
Its a 4 cylinder.

My mother took the car to Autozone on my recomendation. I would hope that the guy reading the code would be smart enough to sell her the right sensor...(wishfull thinking),,,, Is the Cat sensor the same? If so, would be nice if I could swap the old front sensor provided the front one was good... Or, maybe they are both bad?

Nah bro... the I4 has two O2 sensors, Upstream sensor and Downstream sensor.

The Downstream sensor is on the Catalyic Converter, it serves no other purposes other than emission purposes.

The Upstream sensor 'aka' Primary sensor 'aka' Air/Fuel Ratio sensor is on the bottom of the exhaust manifold.

Did you try disconnecting the battery?

Drew03Accord
02-05-2011, 05:00 AM
Its a 4 cylinder.

My mother took the car to Autozone on my recomendation. I would hope that the guy reading the code would be smart enough to sell her the right sensor...(wishfull thinking),,,, Is the Cat sensor the same? If so, would be nice if I could swap the old front sensor provided the front one was good... Or, maybe they are both bad?

The issue might be the sensor you bought. For one, you cant buy the OEM sensor at Autozone so the Bosch sensor is not OEM. Search around and you will see that some people have had immediate trouble using the Bosch sensor. When I changed mine years ago, I purchased it from a Honda dealer online. It was roughly $65 + ship. Wish I had the part number for u, but again, do a search.

Oh, and driving the car with the new sensor made the CEL disappear.

drozzin
02-05-2011, 05:46 AM
How much does Bosch sensor cost? Is it upstream or downstream? AFAIK the only sensor that works reliably on Hondas is Denso.

nehonda
02-05-2011, 07:06 AM
The upstream and downstream sensors are different and not interchangable.
Always remember the parts store guys get paid to sell parts - not to diagnose your problems. And the parts they want to sell are the brand they carry - not always the best one for your car. If you are not well versed on modern car diagnostics they can really take advantage of you. As this sales guy aparently did.
If you kept your old O2 sensor, I would recommend putting it back in and try to get a refund on the Bosh sensor. Tell your story to the store manager if the counter guy baulks.
Car forums like Drive Accord are very useful to research problems before you go parts shopping - not after.

redbug2
02-05-2011, 10:40 AM
Mothers car is 20 miles away, will disconnect battery provided she can find her radio pin key. My father may have one of those reset computers. Blows me away that Bosch builds a product that us faulty? Still hoping that resetting the computer may solve it.

If it fails I will surely attempt to take it back.

Accordriver
02-05-2011, 11:26 AM
Bosch sells an OEM direct fit for most cars. It isn't so much that the sensors are faulty- just that they don't seem to function quite as well as the Honda OEM sensors in Honda cars (different specs, different tolerances etc.).

CYANiDE
02-05-2011, 11:33 AM
Denso makes the OEM sensor for our 7th gens I believe.

redbug2
02-07-2011, 04:18 PM
OK, got my father's code reader, P0141. Tried resetting the code, turned the check engine light off, then, when I started it, light came back on again. Apparently P0141 is the downstream sensor based on other answers I found on the net, so, looks like my mother was sold the wrong sensor.... Now what? Or, could they both have been bad? I doubt it... I wonder if Autozone will make good. It was $100.

NightMarcher01
02-07-2011, 04:27 PM
OK, got my father's code reader, P0141. Tried resetting the code, turned the check engine light off, then, when I started it, light came back on again. Apparently P0141 is the downstream sensor based on other answers I found on the net, so, looks like my mother was sold the wrong sensor.... Now what? Or, could they both have been bad? I doubt it... I wonder if Autozone will make good. It was $100.

I told you bro... and yes just talk to the manager and tell him what happened. I hope you still have your receipt. And I believe the receipt should have the employees name that helped her out.

Downstream sensor is the CAT, so you would have to purchase the post cat o2 sensor.

My suggestion would be to look on Ebay or Craigslist before buying a new one. That's what I did, Primary sensor (wideband) would have cost me over $150 just for it. So I went on Ebay, and bought one for 20 bucks!

redbug2
02-08-2011, 06:31 AM
Nightmarcher1, yes, you called it right. I think my initial plan was sound, and the part they sold us seems to work, its just that Autozone did a bad diagnosis and sold us the wrong part... Anyway, picking up the car tonight, putting the old sensor back in. Called Autozone, told them about my dilema, sales rep was not that articulate, he said to bring it back, we will see what happens when I get there... When they realize that I don't want to exchange, I want to swap for the other one...

Could both have gone bad? Maybe Autozone called it right... If both were faulty would reader show both codes or just stop at the first faulure? If I put the old one back in and get another code indicating its faulty then I'll just go local and get the cat sensor. (I doubt that's the case)

I believe I can get the Cat sensor out without dropping the pipe, so I will take some tools to my mothers to finish the job in her driveway after I get the new part.

Yes, ebay would be cheaper, but I don't have the time to wait, plus I will get a 90 day warranty with the part which is something. Also, in the time I'd be waiting for the part if something really bad goes bad with the engine and there is no way to know because of faulty indicator that would ****...

I'll let you know how it goes.

Accordriver
02-08-2011, 09:46 AM
Nightmarcher1, yes, you called it right. I think my initial plan was sound, and the part they sold us seems to work, its just that Autozone did a bad diagnosis and sold us the wrong part... Anyway, picking up the car tonight, putting the old sensor back in. Called Autozone, told them about my dilema, sales rep was not that articulate, he said to bring it back, we will see what happens when I get there... When they realize that I don't want to exchange, I want to swap for the other one...

Could both have gone bad? Maybe Autozone called it right... If both were faulty would reader show both codes or just stop at the first faulure? If I put the old one back in and get another code indicating its faulty then I'll just go local and get the cat sensor. (I doubt that's the case)

I believe I can get the Cat sensor out without dropping the pipe, so I will take some tools to my mothers to finish the job in her driveway after I get the new part.

Yes, ebay would be cheaper, but I don't have the time to wait, plus I will get a 90 day warranty with the part which is something. Also, in the time I'd be waiting for the part if something really bad goes bad with the engine and there is no way to know because of faulty indicator that would ****...

I'll let you know how it goes.

The code should tell you which bank (front or back) and which position the sensor is located in.

NightMarcher01
02-08-2011, 11:26 AM
The code should tell you which bank (front or back) and which position the sensor is located in.

Yup, depending on the scanner, I believe it could either say "Downstream" aka "Bank 2 sensor" or "Upstream" aka "Bank 1 sensor"

Bank 1 sensor code would be P0134

redbug2
02-08-2011, 04:51 PM
Old sensor back in, I'm getting good at this!

Computer read out "P0141". So, upstream sensor still good. Did a dry run on whether I can get the socket on downstream sensor without dropping pipe, I can. Off to Autozone tomorrow, fingers crossed that they will take new sensor back.

redbug2
02-10-2011, 04:43 AM
Visited Autozone yesterday, explained the situation, they returned the wrong sensor no questions asked. They did not even bother opening the returned box. They may sell it again, that's ok, its in fine shape.

Purchased the downstream sensor... This was not an easy plug in. Though, had it been a plug in I think it may have been more work because the wire runs under the passenger seat and I did not have my tools to get at it. Instructions called for splicing the wires. A little bit of work but the connector was designed nicely and everything came together. After putting in the sensor and connecting the wires I reset the P0141 on the computer. Started the car up, no check engine light! I'm done for now, unless this sensor goes bad...

What would this repair have cost my mother at the dealer?

Thanks,

redbug2

golftango
02-10-2011, 07:14 AM
The issue might be the sensor you bought. For one, you cant buy the OEM sensor at Autozone so the Bosch sensor is not OEM. Search around and you will see that some people have had immediate trouble using the Bosch sensor. When I changed mine years ago, I purchased it from a Honda dealer online. It was roughly $65 + ship. Wish I had the part number for u, but again, do a search.

Wrong.

Only the Bosch "universal" type can give our Accords issues. The direct replacement Bosch and Denso sensors are one in the same, made my the same company here in the states. One is put in a Bosch box, the other Denso.

http://members.cox.net/golftango29/O2senCompare.jpg

OP, sounds like you have a universal type which needs to go back immediately. There is no "splicing" wires and the only tool you'll need are ramps/jackstand and a O2 sensor socket.

Unclip all the clips holding the wire to the frame, follow to the rubber grommet and pop it out. Put the pass seat all the way forward and pull the carpet back and look for the grommet. There is a simple connector there which the replacement sensor will match exactly. The direct replacement Bosch sensor matches the OE exactly, clips, connector and grommet.

NightMarcher01
02-10-2011, 10:53 AM
Visited Autozone yesterday, explained the situation, they returned the wrong sensor no questions asked. They did not even bother opening the returned box. They may sell it again, that's ok, its in fine shape.

Purchased the downstream sensor... This was not an easy plug in. Though, had it been a plug in I think it may have been more work because the wire runs under the passenger seat and I did not have my tools to get at it. Instructions called for splicing the wires. A little bit of work but the connector was designed nicely and everything came together. After putting in the sensor and connecting the wires I reset the P0141 on the computer. Started the car up, no check engine light! I'm done for now, unless this sensor goes bad...

What would this repair have cost my mother at the dealer?

Thanks,

redbug2

:lmao: Most likely an arm and a leg, and maybe your College Tuition on top of it.