The dreaded check engine light!

[scdmarx]

What an awesome group we have here!
Before posting this morning I Googled the code and got all sorts of random answers, non specific.
Nothing like the info I got from you all in less than 2 hours after posting!

So......A couple more questions,

my favorite auto parts dude says there's 4 of these little bastards on my 06 Chevy Express 4.8 3/4 ton.

The exact code I'm getting is "H02 Bank 2 Sen1 Heater Resistance"
He says that code means side with cylinder number 2 and on the engine side of the Cat.
Is this correct?

Yes, Bank one is the side where cylinder #1 lives. Bank 2 is the side where cylinder #2 lives. On any v motor.
Sensor 1 is before the cat, sensor 2 is after the cat.

 

[scdmarx]

Hey wait a minnut! Before you said B2S2.
Now you're saying B2S1.
I hope you're changing the correct sensor????????

 

[scdmarx]

OK, AApples post describes P0059 as B2S1.

I was completely confused!

Sorry 'bout all this.

 

[dan filipi]

Would this thingamajigger affect the warm idle?
It seems to be idling a tad slower.

I really don't think the 02 heater would do that. I'm afraid to rule it out because I've seen stranger things.
I am totally assuming that when you said the light came on again that it was the same code?
How much lower is it idling? Enough to stall at stops? Does it go below 500-550 rpm in gear with your foot on the brake?
If it still acts ok, but you just notice a little bit lower idle than it had before, it could just be that you reset something back to default when you disconnected the battery. (?)

My mistake on the exact code earlier, it is B2S1.

It doesn't stall, no not that much lower.
Just a small amount like how you can feel a seat of the pants difference how it's running.
Maybe it is running on a default or something, it's running great otherwise.

Good point about the error reason each time, I didn't have access to the reader the first time so I can't say.

I reset it with the reader yesterday morning after I got the code, check engine hasn't popped up yet.
Driven maybe 50 miles and a dozen or more starts. I think it took 3 days or so to come on the second time.

 

[cooltech]

on average it takes three complete drive cycles that means upto operating temp each time
and yes bank 2 sensor 1 is before the cat on passenger side

 

[dan filipi]

on average it takes three complete drive cycles that means upto operating temp each time
and yes bank 2 sensor 1 is before the cat on passenger side

Cool, that's the one I'll replace then but I'll wait til it comes on again and read the error to confirm the same.

 

[Riding a Relic]

The heater just helps the ECM begin to read O2 levels earlier for fuel control. Check as scdmarx says, check for voltage and ground at connector. Should be a .5 volt bias with key on on one circuit, 12 volts and a ground on other. O2 sensors don't begin to read very well until the engine heats up and at least 300 degrees hits the 02 sensor before it begins to monitor the fuel and air coming out of the cylinders.

Yeah, I am an instructor as well as spin wrenches.

 

[Riding a Relic]

Bank two sensor one should be the right side of engine, the one closest to the manifold.

 

[dan filipi]

It still hasn't popped an error, not in a rush to spend $100 for a new sensor so I'm waiting for it.
This one is a beeatch to get to also.

Thanks for all the info guys!

 

[Riding a Relic]

Don't buy one till you check the circuits. You have to go through what is called a "drive cycle" to get everything to self test. The PCM is constantly self testing all sensors.

 

[dan filipi]

Don't buy one till you check the circuits. You have to go through what is called a "drive cycle" to get everything to self test. The PCM is constantly self testing all sensors.

Drive cycle?
Is this something it will do on its own or do I have to run something?

 

[slabghost]

Just keep driving it is all you need do.

 

[scdmarx]

Don't buy one till you check the circuits. You have to go through what is called a "drive cycle" to get everything to self test. The PCM is constantly self testing all sensors.

Drive cycle?
Is this something it will do on its own or do I have to run something?

Like slabghost said, drive it a couple days. It's that simple.

"The PCM calculates the heater resistance on a cold start. This diagnostic will only run once per ignition cycle."
"CONDITIONS FOR SETTING THE DTC
The PCM detects that the affected HO2S heater calculated resistance is not within an expected range at engine start-up for 1 second."
viewtopic.php?p=77494#p77494

 

[Ansimp]

Drive cycle is the one after the rinse cycle :smilie_happy:

 

[dan filipi]

It's been a week running every day and still no light.

I hate when stuff does this to me.

 

[Ansimp]

Praise the gremlins " it's healed"!

 

[slabghost]

Keep watching and driving. It will return. It's just giving you a little time to save up.

 

[toytender01]

I have found that on my vehicals they throw a check engine light after a lot of stort trips with lights and heater on. :head bang: the longet I do this the more codes the computer builds. :head bang: :head bang: Once the batt builds up and after enough starts the computer will erase the codes one at a time. :Egyptian: I just reset the computer now myself . :cheeky: I would worry if it throws a different code. :swoon: :swoon:

 

[dan filipi]

Now I'm confused.

The light came on again but this time it's sensor 2, same side where before it was sensor 1 :headscratch:

Could it be 2 O2 sensors are failing?

 

[scdmarx]

Now I'm confused.

The light came on again but this time it's sensor 2, same side where before it was sensor 1 :headscratch:

Could it be 2 O2 sensors are failing?

Anything's possible, many things not likely?????
Are you sure it was the other one last time and a different one this time? Too many things called "02 sensor" can get a little confusing.

Wish I was there. :head bang: