The P0131 code says Heated O2 sensor, low voltage.

Yesterday, I checked the connection and there is small amount of oil running down the connection that connects to the O2 sensor. (I used to have a small oil leak somewhere above the oil pan, but the problem was fixed a month ago after I added some stop leak to it.) I removed the o2 sensor and could see oil inside the connection. I sprayed it with degreaser, cleaned it with q-tips, and let it dry for a few hours. After putting it back together, the CEL stay off for about 1/2 a mile. I plan on getting more in depth with the issue this weekend, but I wanted to see if anyone else has had this problem

 

oil will interfere with electrical signals

Do a full system reset by pulling the CLOCK fuse on passenger end of dash for a minute then reinsert
that forces a master ECU reboot and relearn,,drive it `normal for you` for a week then have the codes ckd at any big parts store
for free!

You did right to clean it!--you can use CRC electrical cleaner or similar to rid oil, get the wire and terminal ends clean-sandpaper if needed to remove crud,
use carb cleaner or simple green-other degreaser---to get rid of all traces of the oil drips in the area
Its still leaking if there is fresh oil afterwards

where was it leaking from ??? not much to go wrong on the TL!
you may alert the rest of us to a new problem~

 

After cleaning apply some dielectric grease to keep corrosion from forming & water out.

 

Your front o2 sensor is bad. Replace with a new one.

I had the same problem, it shown oil in it, I had no idea where the oil came from and I have no leaks. I don't know if it was luping oil or oil was dripping in from the o2 wires, the wires seemed to be clean and dry. I cleaned out the oil, but didn't help. I replaced the o2 and problem was fixed.

 

I did do a reset after I cleaned everything; I forgot to mention that.

acutee,
I will replace the sensor and see what happens. I've read not to get Bosch, but to get Denso...does that sound correct?
After doing a google search of "Honda P0131", it seems that people were still getting the code after replacing the o2 sensor, which is why I created this thread. Since you say it worked for you, I will replace it and report back.

 

There could be some other issues related with this code, like exhaust leaks, or like too lean or too rich. Most people didnt have luck with bosch, denso is the best option. Since it is expensive, you need to do further testing before purchasing it. you can test the voltage on the o2 connector with a voltmeter or if you have obd2 to look at o2 volt, at least it helps to decide if the o2 is bad or not. Do you know if you are losing more gas than before with the p0131?

 

I did see that Denso is more expensive that why I'm planning on looking into the issue a bit more this weekend. If it turns out that the O2 sensor is fine, what should I do next?

The CEL came on Sunday and I filled up yesterday. MPG was 20.5, but it is normally 22-23. So yes, slightly less.

 

dont buy anything yet- get a code scan from parts store-
test and diagnose unless you have money to throw away,,
Im sure at some point it will need a coil- so replacement of 6 now will be a good idea~Sir~

denso is the OE brand- stay with it, and it will plug and play
reset ecu again if you replace O2

 

have you cleaned the egr ports yet? every 75kmiles they plug up and effect mileage and running

 

When the CEL came on, I had Autozone scan it. The result is the P0131 code.

Yes, I cleaned the egr ports back in February. However, I put the intake manifold cover gasket on the wrong way. So for the past few months I've been trying to diagnose the vibration I was having. After multiple searches on here, I realized my problem and put the gasket on correctly. So for about 3 weeks my car has been running great, until this problem started.

 

what about the oil leak- where was it from and what did you do to fix it?

was there fluid-what type, on the O2 inside parts? or just the outer electric connection?

that gasket on the cover tricks a lot of people- easy to put on upside down

have the codes ckd again now that you worked on it and reset ecu
codes are clues not diagnosis

 

I never could tell exactly where the original oil leak was from. It was somewhere above the oil pan. I used some type of oil stop leak stuff.

There seemed to be oil on the outside of the wires/cable that the O2 sensor connects to. There was also oil inside the connections, both the O2 cable and the one it connects to.

On my way home, I'll get the codes checked again.

 

ok so just the outside had oil --no prob

 

Not sure what happened but over the weekend the CEL went away and the car is running fine.

Thanks for the help anyway

 

Is there a DIY with pictures, to replace the O2 sensor
on Acura TL. Would someone post one if there is none.

Thanks,

 

follow wire to sensor by cat- there is a front and rear sensor- front most common failure
use `sensor removal wrench` or maybe a wrench or socket will fit it, i dont recall how much room to work there

apply a dab of spark plug anti seize to the threads of new part so it goes in easier.
get denso brand sensor- plug and play since they are the oe part supplier on these

 

did you look in the diy thread list?
its located on main thread list page - a couple down from the top- `Official gen2 diy thread list`- posted by fsttyms1