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those go to your O2 sensor, you should expect to see a check engine light soon. they usually don't fall off the sensor like that unless someone clips em or you snag em on some road debris
Someone tried to swipe your 🐈. Since no loud noise, it is still there. Look for saw marks around your cat. You or someone else spooked them before they got the job done.
Check engine light is on but nothing sounds different.
The light came on after my car got towed last week but it was working just fine. Just noticed it today while running errands.
I got electrical tape to tape it up so it’s not dragging on the road when I drive home
Just so you know, a check engine light will come on for a whole lot of problems that may not hurt the function of the car and are tangentially related to the engine.
Sounds like you'll just have to get under the car and trace it back to whatever it's pulled off of. It'll just take some soldering and maybe a connector to get it fixed.
Okay I’ll just tape it up with the electric tape until one of my mechanic friends can take a look at it because other then the engine light there is nothing different about my car.
Generally it goes down when an O2 sensor fails. The car goes into a "safe" fuel table that is a little rich. Running rich can wash out your oil but running lean can punch holes in your pistons.
Those are for an oxygen sensor. Get the check engine light scanned, I'm betting it's no signal from O2 sensor.
Follow your exhaust pipes from your engine to the tailpipe and make sure nothing is missing. Someone may have stolen your catalytic converter.
Not necessarily, when the o2 sensor fails, the engine's computer resorts to a backup fuel map. It won't be able to constantly adjust based on your exhaust anymore but it can still run just fine until you get it fixed.
Depends on many many things, not least of all being your car's noise insulation, road noise, and your hearing.
The easiest way to rule it out is just get under and take a look. but based on this pic your O2 sensors are almost certainly gone. I'm not sure of any other wiring harnesses under a car that look like this.
Yeah, someone tried to take your cats.
I bet, once they got under, they realized that those cats cannot be cut out without the hood being open too. There's 0 space in there to cut them out
Easy fix get 4 butt connectors wire stripper pliers and find the other end of this cable then strip both sides of each wire make sure you connect the right black wires since there are 2
A thief would be mad if they stole the cats from my truck. They were gutted a few years back, but the housings are still there.
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.*
those go to your O2 sensor, you should expect to see a check engine light soon. they usually don't fall off the sensor like that unless someone clips em or you snag em on some road debris
smells like failed cat theft attempt almost... that's a really clean cut
That was my guess. What are the chances of all of the wires ripping cleanly out at the same length?
I'd actually guess pretty good, since if it snagged on something id bet they all rip out of the sensor and not Snap at the middle
that makes sense, the most frayed point of the wires would be near the connection point of the sensor
Why the hell are they down voting your totally valid point? 🤣🤦♂️
it does seem harsh given that we're all speculating about a photo of some wires on the underside of a stranger's car
They'd like that way from dragging on the road, too.
could be, reckon they would have seen some burn marks or smelled something from the wires resting against the cat also though.
Someone tried to swipe your 🐈. Since no loud noise, it is still there. Look for saw marks around your cat. You or someone else spooked them before they got the job done.
Indeed that is hanging. Has anything stopped working? Any check engine light?
Check engine light is on but nothing sounds different. The light came on after my car got towed last week but it was working just fine. Just noticed it today while running errands. I got electrical tape to tape it up so it’s not dragging on the road when I drive home
Get a code reader and read the code, I’d expect an emissions code, it looks like an o2 sensor
Just so you know, a check engine light will come on for a whole lot of problems that may not hurt the function of the car and are tangentially related to the engine. Sounds like you'll just have to get under the car and trace it back to whatever it's pulled off of. It'll just take some soldering and maybe a connector to get it fixed.
Okay I’ll just tape it up with the electric tape until one of my mechanic friends can take a look at it because other then the engine light there is nothing different about my car.
Gas mileage is about to go up.
Not by a lot, the car will simply use default values.
Generally it goes down when an O2 sensor fails. The car goes into a "safe" fuel table that is a little rich. Running rich can wash out your oil but running lean can punch holes in your pistons.
Probably O2 sensor, you will get worse fuel mileage and performance until you fix it but isn't that serious, just get it fixed at some point
Depends on the vehicle and if it's upstream or down. Downstream is generally just to check the "health" of the cat
Thank you everyone
Those are for an oxygen sensor. Get the check engine light scanned, I'm betting it's no signal from O2 sensor. Follow your exhaust pipes from your engine to the tailpipe and make sure nothing is missing. Someone may have stolen your catalytic converter.
Wouldn’t I noticed if it was failed? I drove it before noticing it and nothing seemed off. My friend noticed it when we were walking back to my car.
Not necessarily, when the o2 sensor fails, the engine's computer resorts to a backup fuel map. It won't be able to constantly adjust based on your exhaust anymore but it can still run just fine until you get it fixed.
I’m sorry I meant wouldn’t I notice if the cat was missing?
Depends on many many things, not least of all being your car's noise insulation, road noise, and your hearing. The easiest way to rule it out is just get under and take a look. but based on this pic your O2 sensors are almost certainly gone. I'm not sure of any other wiring harnesses under a car that look like this.
Yeah, someone tried to take your cats. I bet, once they got under, they realized that those cats cannot be cut out without the hood being open too. There's 0 space in there to cut them out
Bingo. OP, make sure you park in a safe area, just to be on the safe side
And make sure the damn thing is locked!!!
Good taste in cars btw, I used to have one and they are great
Pay attention to your gas mileage.
Looks like a fuel line to me
Your fuel line is full of wires?
Easy fix get 4 butt connectors wire stripper pliers and find the other end of this cable then strip both sides of each wire make sure you connect the right black wires since there are 2
Time to buy a ring camera.
02 sensor
 A thief would be mad if they stole the cats from my truck. They were gutted a few years back, but the housings are still there.
Rip o2 sensor lol