Help with O2 location

1996 Chevy Blazer 4.3 2wd....

Hi,

Looking under the car to locate the sensors, I see four of them. My scanner says: B1-S1, B1-S2, B1-S3, and B2-S1. I figure the last one, B2-S1 is after the catalytic converter, but the others; I am not sure of .

This engine has a duel exhaust coming out of it and one sensor in each of the pipes. Where the duel exhaust meets the single pipe (before the CC) there is another sensor.

How do I know which is which?

Thanks Hank from PA

Reply to
Hank
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B-1 = 'Bank one', the bank of cylinders that starts closest to the front of the vehicle

in your case, driver's side

Reply to
Gary Glaenzer

Hank,

B2-S1 is the pre-cat (BEFORE, not AFTER the CC), passenger side sensor.

Doc

Reply to
"Doc"

Thanks for the answers but I'm still unsure of the name for each one when I am under the car. Example, if I wanted to change Bank 1 Sensor one is it the first sensor on the left or right side of the engine. (I have duel exhaust coming out.) I think you can understand where I am coming from

Hank from PA

Reply to
Hank

Thanks to all this is the answer I needed to know: B1S1= driver side upstream B2S1= passenger side upstream B1S2= after Y, ahead of cat-con B1S3= post cat-con

Hank from PA

Reply to
Hank

Start at the exhaust manifold from the cylinder head and follow it towards the back of the truck.

Driver's side, the first sensor you'll hit (BEFORE cat) is B1S1. On the same side, the next sensor you'll find (AFTER CAT) is B1S2

Passenger side, first sensor (BEFORE CAT) is B2S1, next one (AFTER CAT) is B2S2.

Doc

Reply to
"Doc"

Doc, thanks,

Now I have conflicting information.

My Auterra scanner labels the O2 as follows: B1-S1, B1-S2, B1-S3, and B2-S1.

From under the car there is only one sensor after the catalytic converter; the other 3 are: one on the top sides (each side) of Y and one on the bottom of the Y.

You claim, Doc, that anything after the "cat" gets a S2 label along with passenger side Y gets a S2.

Another response claims different and now I am con fussed again....I can't find any reference to this topic anywhere.

Hank from PA

Reply to
Hank

(which way did he go.......which way did he go) . On Tue, Sep 16, 2003, 11:55am (CDT+5) snipped-for-privacy@ptd.net (Hank) writes.....

Doc, thanks,

Now I have conflicting information. My Auterra scanner labels the O2 as follows: B1-S1, B1-S2, B1-S3, and B2-S1. From under the car there is only one sensor after the catalytic converter; the other 3 are: one on the top sides (each side) of Y and one on the bottom of the Y. You claim, Doc, that anything after the "cat" gets a S2 label along with passenger side Y gets a S2. Another response claims different and now,

I am con fussed again....

I can't find any reference to this topic anywhere. Hank from PA . Hank, You're confused? How bout me? (your words...if I may....somewhat edited)

"Looking under the car to locate the sensors, I see FOUR of them............. This engine has a duel exhaust coming out of it and ONE sensor in EACH of the pipes. Where the duel exhaust meets the single pipe (before the CC) there is ANOTHER sensor."

now Hank....my addition ain't dat good. But that wording adds up to 3 sensors. Where is the 4th one your looking at?

any whooo....... Hook yer scanner up....clear the codes.... obtain "closed loop" unhook the sensors one at a time to set a code....get yer code....recconect the sensor and repeat the process fer each sensor..... yer scanner will clear the confusion up for you.

ignorance ain't always bliss.....

respectfully Scribb Abel

in a pinch......a wet booger that is allowed to dry for a period of time.......makes a great adheasive

Reply to
Scrib Abel

Since it's an OBD2 vehicle, the logical place would be at the outlet of the cat. (B1S3)

Reply to
Neil Nelson

I think I must use the "disconnect and check" method.

Four sensors. Three before the Cat and one after.

Thanks Hank from PA...

Reply to
Hank

. (thread recap.......Hank owns a scanner... Hank has an 02 code.....Hank sees 4 sensors ....Hank don't know which one set the code... ....Hank don't need no stinking books.... ....Hank admits confusion.... .....Scrib amits confusion.... .....Doc and Gary make Hank crawl under the vehical 3 times.........)

(showing signs of growth in his diagnostic abilities)

On Wed, Sep 17, 2003, 9:58am (CDT+5) From: snipped-for-privacy@ptd.net (Hank) decided to use proven diagnostic techniques...and informed the group of this.........

I think I must use the "disconnect and check" method.

Four sensors. Three before the Cat and one after.

Thanks Hank from PA... ..

Hank, I think you must too.

Scribb Abel ~~wonders if Hank will test the sensor behind the convertor first.....or after he finds the other three are good~~

In a pinch...............wet boogers make for a good adhesive.......when allowed to dry for a period of time.

Reply to
Scribb Abell

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