Gotta get smogged- CEL on (o2 sensor)

blackmax

New member
It's been on for like 80,000 miles (on and off) and is apparently not an issue....except to get smogged. Last time, I disconnected the battery and drove the 50 or 60 miles. The light never came back on ...and I passed smog. Now, it's back on and I have to get it smogged soon/now.

Tips tricks? My emissions are fine; it's just that the CEL is an auto-fail. If I just turn it off, I think the computer at the smog knows that and won't even test me...right?
 
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It's been on for like 80,000 miles (on and off) and is apparently not an issue....except to get smogged. Last time, I disconnected the battery and drove the 50 or 60 miles. The light never came back on ...and I passed smog. Now, it's back on and I have to get it smogged soon/now.

Tips tricks? My emissions are fine; it's just that the CEL is an auto-fail. If I just turn it off, I think the computer at the smog knows that and won't even test me...right?

I gotta say I like your style. Start one post asking about things we should be doing to get 300,000+ miles out of our 4Runners, then another post about leaving a check engine light on for 80,000 miles.

Play on playa.
 
I gotta say I like your style. Start one post asking about things we should be doing to get 300,000+ miles out of our 4Runners, then another post about leaving a check engine light on for 80,000 miles.

Play on playa.

how does a CEL for a fault that doesn't really exist (in reality)...for an o2 sensor which is not really faulty affect drive train life? It doesn't. But it can allow a mechanic to vacuum thousands of $$$ out of someone's pocket, chasing a problem that isn't really there. Not always, but quite often.

I personally know people who have spent over $2,000 on parts and labor....but but but, the light is still on.
 
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Clearly something is wrong. What is the code? If it is for an o2 sensor, what about it? Is it the heater circuit code?

I suspect it is the heater circuit in an O2 sensor. Just replace the 02 sensor and be done worrying about it.
 
how does a CEL for a fault that doesn't really exist (in reality)...for an o2 sensor which is not really faulty affect drive train life? It doesn't. But it can allow a mechanic to vacuum thousands of $$$ out of someone's pocket, chasing a problem that isn't really there. Not always, but quite often.

I personally know people who have spent over $2,000 on parts and labor....but but but, the light is still on.

Who? And why? Most states have price ceiling exemptions. If you can prove you have spent X then they grant an exemption.

As for why an o2 sensor fault would be bad: o2 sensors help the car maximize the combustion cycle. A faulty o2 sensor will cause the engine to run "bad" in regards to emissions. In some situations, a faulty o2 sensor will cause a car's ECU to throw it into dummy mode. The car will run in a dummy state which will impact fuel economy and emission quality.

You might notice worse MPG, for example, if the car can't determine how much to lean/rich the cycle or etc, etc.
 
Clearly something is wrong. What is the code? If it is for an o2 sensor, what about it? Is it the heater circuit code?

I suspect it is the heater circuit in an O2 sensor. Just replace the 02 sensor and be done worrying about it.

It's P0136. I guess that's driver side downstream?
 
Who? And why? Most states have price ceiling exemptions. If you can prove you have spent X then they grant an exemption.

As for why an o2 sensor fault would be bad: o2 sensors help the car maximize the combustion cycle. A faulty o2 sensor will cause the engine to run "bad" in regards to emissions. In some situations, a faulty o2 sensor will cause a car's ECU to throw it into dummy mode. The car will run in a dummy state which will impact fuel economy and emission quality.

You might notice worse MPG, for example, if the car can't determine how much to lean/rich the cycle or etc, etc.

I know a person who had an O2 code.....and ended up replacing all 4, at different times....for WELL over $2,000 parts and labor. Rip off? Of course. Guess what....CEL still on.

My light has been on for 80,000 miles. I get 22 mpg highway then and now. It's bogus.
 
Are you sure you are not fudging those numbers? A new 02 sensor is around 80 non-dealer, 160 or so, dealer. 2k for 4 02 sensors? Really? REALLY???? Where they made of gold? What you might be referencing is a whole mess of labor attached to it. Maybe some other stuff had to be done? A rusty exhaust?

FYI: It takes about 2 minutes to replace the downstream 02 sensors on the runner. I know, I have done it.

Anyway. Run to autozone, grab a denso for around 80 and be done with it.
 
Are you sure you are not fudging those numbers? A new 02 sensor is around 80 non-dealer, 160 or so, dealer. 2k for 4 02 sensors? Really? REALLY???? Where they made of gold? What you might be referencing is a whole mess of labor attached to it. Maybe some other stuff had to be done? A rusty exhaust?

FYI: It takes about 2 minutes to replace the downstream 02 sensors on the runner. I know, I have done it.

Anyway. Run to autozone, grab a denso for around 80 and be done with it.

I know....I've done it too. I just don't want to replace something that isn't broken. I'll buy the $20 sensor and see where it gets me.
 
Just had mine smoged cpl days ago , passed once its cleared in Nv your good (cel) mines been coming on about every 5 tanks of gas I know it's one of the upstream because I replaced both rears which I purchased on amazon for I think 55$ . Those are o2 , front are air/fuel which are more like 130$ ish in amazon . So not sure about 2,000$ ? Go to o'reilys & have them read it for ya then clear it . I go to jiffy smog on jones & charleston never not passed for 23$ !!!! Buy denso
 
Yea. Buy Denso.

Don't get the 20 dollar ones. The issue is, the sensor transmits data to the ECU via voltage level. The ECU is set to translate what a particular voltage means. We are talking .000 place voltage levels and the difference of a 100th of a decimal can pop a code.

The 20 dollar ones, well, are 20 bucks for a reason and they are crap. They usually don't have the ability to transmit discreet voltage like a denso can.

Save yoru 20 bucks. Pay 55 on Amazon and be happy.
 
Yea. Buy Denso.

Don't get the 20 dollar ones. The issue is, the sensor transmits data to the ECU via voltage level. The ECU is set to translate what a particular voltage means. We are talking .000 place voltage levels and the difference of a 100th of a decimal can pop a code.

The 20 dollar ones, well, are 20 bucks for a reason and they are crap. They usually don't have the ability to transmit discreet voltage like a denso can.

Save yoru 20 bucks. Pay 55 on Amazon and be happy.

thanks....already hit the "buy" button though. Oh well. I just want to get past smog for now. Hell, I've been going for years with the P0136 code. Always got 21-22 mpg highway.....and 18 average for 10,000 miles. If it goes again, I'll get the denso.

Thanks much for the tips.
 
I know a person who had an O2 code.....and ended up replacing all 4, at different times....for WELL over $2,000 parts and labor. Rip off? Of course. Guess what....CEL still on.

My light has been on for 80,000 miles. I get 22 mpg highway then and now. It's bogus.

Are you sure you are not fudging those numbers? A new 02 sensor is around 80 non-dealer, 160 or so, dealer. 2k for 4 02 sensors? Really? REALLY???? Where they made of gold? What you might be referencing is a whole mess of labor attached to it. Maybe some other stuff had to be done? A rusty exhaust?

FYI: It takes about 2 minutes to replace the downstream 02 sensors on the runner. I know, I have done it.

Anyway. Run to autozone, grab a denso for around 80 and be done with it.

Well now you both know someone that spent a ton of money on the O2 CEL....me

I spent $1425 for both cats, all four sensors, all 16 head studs, all 16 head bolts, and both exhaust manifold gaskets. and i used pacesetters for my V8.

Still got a CEL p0430 after everything was done. ended up doing a O2 fooler mod for $5 and its been off for the last 3500 miles. Fuel economy is up too. I dont know how people drive with the CEL, VSC and TRACs light on all the time. 3 lights not 1, its a bit annoying, plus tracs doesnt work so thats not good in bad weather.

Was is worth it? Yes, i had leaky manifolds already. I had bad fuel economy already. My vehicle has 164k when i got it. I expected to dump some coin at it so it can hit the 300k mark. The trans was replaced at 145k, so as long as it runs good, i dont see why not.
 
Well now you both know someone that spent a ton of money on the O2 CEL....me

I spent $1425 for both cats, all four sensors, all 16 head studs, all 16 head bolts, and both exhaust manifold gaskets. and i used pacesetters for my V8.

Still got a CEL p0430 after everything was done. ended up doing a O2 fooler mod for $5 and its been off for the last 3500 miles. Fuel economy is up too. I dont know how people drive with the CEL, VSC and TRACs light on all the time. 3 lights not 1, its a bit annoying, plus tracs doesnt work so thats not good in bad weather.

Was is worth it? Yes, i had leaky manifolds already. I had bad fuel economy already. My vehicle has 164k when i got it. I expected to dump some coin at it so it can hit the 300k mark. The trans was replaced at 145k, so as long as it runs good, i dont see why not.

Yikes....yea, they'll chase a ghost as long as they think you have room on your credit card.
 
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Update- Pulled the O2 sensor last night. Heated it up to slightly glowing red (propane torch)...then quenched in water. Did this 3 times. Re-installed and have driven 45 miles so far. The lights (CEL and VSC) remain off. 45 miles should be enough for 2 cycles for the computer. So.....I should be good.

For how long? who knows.
 
Update- Pulled the O2 sensor last night. Heated it up to slightly glowing red (propane torch)...then quenched in water. Did this 3 times. Re-installed and have driven 45 miles so far. The lights (CEL and VSC) remain off. 45 miles should be enough for 2 cycles for the computer. So.....I should be good.

For how long? who knows.

Did you heat the tip? What does the heating and quenching do, clean the tip?
 
Did you heat the tip? What does the heating and quenching do, clean the tip?

theory is that is COULD cause the carbon coating to shatter/break loose, thus cleaning the surface. I figured that was a real long shot...but had the thing out, and a torch handy...so gave it a shot. The light is still off.....for now
 

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