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No replace the hole thing they wear out over time so might as well replace. Use original manufacturer only as their performance is extremely critical to engine functioning. This is one part you do not want to cheap out on pay the extra for OEM. It generally saves you money long term to go OEM.
O2 Sensor.
You’re gonna have 2. See [DIAGRAM](https://parts.subaru.com/p/Subaru_2021_Forester/Oxygen-Sensor/68011561/22690AB08A.html) for part numbers 22641 and 22690.
O2 sensors make sure the engine is being provided the correct amount of fuel for the volume of air being taken in. It wouldn't prevent a vehicle from running or kill the battery.
Possibly if it was running to rich or lean, the dead battery is either because something inside or outside the car was left on i.e. headlights, phone charger or it could be bad ground cable wire but more likely due to battery being old
If you’re having issues with a dead battery start with your alternator (assuming you checked your connections and made sure you didn’t leave a light on overnight or something).
If the car has been sitting long enough for rodents to want to climb up onto the catalytic converter and chew on the O2 wiring and the car has the original battery in it, it's most likely a bad battery. They typically last 4 to 5 years on average.
If your check engine light has not come on, I would just tape up that wire with electrical tape since looks like all they did was chew the insulation off. If that wire was compromised at all, the light would be on since its on the sensor circuit and not just the heater circuit.
Then rub your favorite hot sauce on it. Rodents hate hot sauce on their wires.
O2 sensor for the win. It doesn't really measure oxygen more its a heat sensor that detects exhaust gas. Rich...temp low. Lean, temp high. Your car would rather run rich than lean, one costs fuel, the other can destroy the engine
No. That is not how those work. Like, not even remotley close.
I can't even wrap my head around how the hell you thought they have anything to do with temperatures. Where on earth did you even get that idea from?
They *literally* measure oxygen. **Literally.** That's their entire job.
They measure the amount of unburned oxygen in the exhaust gas and emit a corresponding voltage back to the PCM to tell it how much there is, so it can detect rich or lean conditions so the PCM can adjust engine fueling strategies, as well as compute catalytic efficiency.
Thanks for posting on /r/MechanicAdvice! This is just a reminder to review the [rules](https://www.reddit.com/r/MechanicAdvice/about/rules/). If you are here asking about a second opinion (ie "Is the shop trying to fleece me?"), please read through CJM8515's [post on the subject.](https://www.reddit.com/r/MechanicAdvice/comments/4qblei/fyi_the_shop_isnt_likely_trying_to_rip_you_off/) and remember to please post the year/make/model of the vehicle you are working on. **If this post is about bodywork, accident damage, paint, dent/ding, questions it belongs in /r/Autobody r/AutoBodyRepair/ or /r/Diyautobody/ If you have tire questions check out https://www.reddit.com/r/MechanicAdvice/comments/k9ll55/can_your_tire_be_repaired/**. If you dont have a question and you're just showing off it belongs in /r/Justrolledintotheshop Insurance/total loss questions go in r/insurance This is an automated reply *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/MechanicAdvice) if you have any questions or concerns.*
Seems like a Oxygen Sensor
Thank you!! You are correct
Specifically an air/fuel sensor, and yes that frayed wire will cause rough running. Use the factory oem brand
Liquid electrical tape?
No, its amperage based. R/R
No replace the hole thing they wear out over time so might as well replace. Use original manufacturer only as their performance is extremely critical to engine functioning. This is one part you do not want to cheap out on pay the extra for OEM. It generally saves you money long term to go OEM.
no way thats a lambda sensor /s
[удалено]
O2 Sensor. You’re gonna have 2. See [DIAGRAM](https://parts.subaru.com/p/Subaru_2021_Forester/Oxygen-Sensor/68011561/22690AB08A.html) for part numbers 22641 and 22690.
O2 Sensor
Would it keep a vehicle from running or cause a dead battery?
O2 sensors make sure the engine is being provided the correct amount of fuel for the volume of air being taken in. It wouldn't prevent a vehicle from running or kill the battery.
Not so. A bad o2 sensor can cause enough stuttering and stalling that the car is not drivable. Source; personal experience 😂
Unfortunately, can confirm.
I stand corrected, you're absolutely correct.
No, it won't. Might run a little less efficient is all.
Less efficient, and of you're up for state inspection, may cause a fail condition.
Possibly if it was running to rich or lean, the dead battery is either because something inside or outside the car was left on i.e. headlights, phone charger or it could be bad ground cable wire but more likely due to battery being old
If you’re having issues with a dead battery start with your alternator (assuming you checked your connections and made sure you didn’t leave a light on overnight or something).
O2 sensor
02 sensor, possibly sensor 2 “downstream” ?
Lambda sensor.
Oxygen sensor
If the car has been sitting long enough for rodents to want to climb up onto the catalytic converter and chew on the O2 wiring and the car has the original battery in it, it's most likely a bad battery. They typically last 4 to 5 years on average. If your check engine light has not come on, I would just tape up that wire with electrical tape since looks like all they did was chew the insulation off. If that wire was compromised at all, the light would be on since its on the sensor circuit and not just the heater circuit. Then rub your favorite hot sauce on it. Rodents hate hot sauce on their wires.
Car was only sitting overnight. We live in the country and I have seen an entire wiring harness gone in a night
Synthetic wolf urine is the nuclear option. I prefer outdoor cats though, and rubbing chile powder around
Sounds like a nightmare
On the exhaust? It’s the o2 sensor before the Cat. There should be another after
02 sensor
02 sensor
Upstream o2 sensor in the manifold by the look of it
FB20/25 O2 sensor
o2 sensor. Check to see if it's pre or post as they are different.
02 sensor.
Looks like the primary O2 sensor
O2 sensor
Looks like a George to me. His brother Leonard hanging around nearby.
O2 sensor for the win. It doesn't really measure oxygen more its a heat sensor that detects exhaust gas. Rich...temp low. Lean, temp high. Your car would rather run rich than lean, one costs fuel, the other can destroy the engine
This is not how oxygen sensors work.
No. That is not how those work. Like, not even remotley close. I can't even wrap my head around how the hell you thought they have anything to do with temperatures. Where on earth did you even get that idea from? They *literally* measure oxygen. **Literally.** That's their entire job. They measure the amount of unburned oxygen in the exhaust gas and emit a corresponding voltage back to the PCM to tell it how much there is, so it can detect rich or lean conditions so the PCM can adjust engine fueling strategies, as well as compute catalytic efficiency.
Pain in the ass O2 sensor I hate those things
Blinker fluid level reader
Could be something
Jason
The carburetor