Oxygen sensor How to tell if it is bad

Can some one tell me if there is a way to tell if the oxygen sensor is bad? without hooking it up to Diagnose ??

 

Are you getting a check engine light?

 

Not OP but I get the code every now and then and then it clears. I've probably had it come up three times now.

 

What’s the code?

 

P0031

 

Thats just the heater circuit. If it goes out I wouldn't worry about it.

 

https://axleaddict.com/auto-repair/How-to-Check-an-Oxygen-Sensor

 

If the MIL (check engine light) is not on, is there a problem?

The FSM has some instructions on checking the resistance of the sensor. A borderline sensor may trip the light on and off for a while, but it will eventually fail. It may also show as a pending code in the mean time. I had a Tacoma fail inspection with a pending O2 code, although the MIL was off at the time, and I though I was good to go.

Most auto parts stores will check your codes for free. A reader for your smart phone is pretty cheap too. Under $20 on ebay.

 

there is a resistance check that can be made on the o2 heaters circuit. a 1 ohm difference is enough to trip the code. Essentially the PCM is expecting to see a certain voltage at a certain time on the heater circuit after the engine is started. I chased this problem on a buddies AMG off and on for a few days until he fessed up and he told me he got the o2 sensors off of ebay and not the benz dealer.

 

CEL was coming on and off and bothering me. I've pulled the diagnostics pages from the online repair manual and I'm going to go through the steps this weekend. Running a brand new OEM O2 sensor right now.

 

If your truck has 100k miles or more then it's time to replace

 

Does anyone know if theres a difference between the Auto and manual o2 sensors for the 5vz? im not sure if it matter but ive also got a cali spec truck

 

CEL cleared on my way to work.... as well as my evap small leak code. I’m still going to do some investigation. Doubt they’re off for good.

 

I’ve been waiting for mine to puke, but they are still going strong-ish. I’ve got 197k on the originals. My cats too. I’m sure they could stand to be replaced. My mileage with the 3.4 hovers around 15 on good day.

Could a dealers diagnostic machine get more detail from the ECU, with respect to the condition? I just passed state emissions the other day.

 

Holy crap guys, they're a maintenance item you know. They start reading false and misleading the computer when the Zircon in the tip gets fouled from too many hours of use. They're like $120, just replace them

 

Factory service manual says check resistance of heater resistance.

at 20°C (68°F) 11 – 16 Ω
at 800°C (1,472°F) 23 – 32 Ω

If its throwing a bad heater coil code i'd replace it. I heard that bank is hard to replace though like you need to take off the exhaust and muffler to get to it.

 

Yes they are. However before dropping 300 bucks on 2 sensors I'd like to know if there's a way to quickly check their functionality. If they are costing me $ with poor milage I'd be more apt to replace them sooner rather than later. If they aren't I'll wait till I get a a code. Three hundred isn't really a lot of money to me, but do I waste it on sensors, or save it for a new Sig Sauer 365, or a CZ 455 for my son? I have kids so....priorities.

 

Those sensor are 20-30 bucks on ebay. 120 bucks is at autozone and they have to pay they're rent. Guess where that 100 goes.

 

I usually stick with OEM for parts due to longevity. A bit more expensive but, shit just lasts...

 

you can get oem for that price on ebay maybe 20 bucks more you just need a good eye or sometimes it says oem. autozone will sell an oem part that cost them 20 dollars and it says toyota oem all over the box and sell it for $150. MAF for example is 25 dollars oem on ebay 150 autozone. Almost all other parts are the same however you can receive non oem parts from not looking into the listing.

Rent is like 2k a month and employees are 2k a month full time. How would you make profit with $20 a part. They have to charge $100 extra or they would go out of business. Most of them just break even and literally shut their doors and go out of business because $100 is not enough. Your not going to have a store in town to get you the parts same day when real estate charges 2k a month for rent on a shit property full of cockroaches. Trust me i know i throw them out daily and move place to place running away from the mother f#c$ers. Most restaurants in my area get shut down due to mice eating the food and its not even an undecent area. Some places are a joke. If you don't want to pay for a total scam "not kidding" go on ebay/Amazon like everyone with a brain but look incredibly careful and ask many questions to make sure it's the same part. As you are basically buying from the Chinese which make a living scam as artists selling thing that don't work.