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· Registered
'06 LGT SWP
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344 Posts
Discussion Starter · #1 ·
Soo i know we have 2 sensors in the stock cat pipe? I was wondering which one is which, theres a front 02 and a rear one, are they both the same?

What is called the one more at the front of the cat (more towards the front of the car)??

What is called the sensor at the end of the cat (The one that triggers the p0420 code)

I need to replace the last sensor, put in a rallytech o2 spacer and seems like its rubbing against the car now, and my wires cut up...

Is there a part #, or are they both the same 02 sensor??

Heres what i have as parts:

BOSCH Part # 15732
4 Wire; Heated; Check / Replace Interval: 100,000 Miles; Universal Type - Downstream
$55.79 $0.00 $55.79

BOSCH Part # 17018 {Wideband A/F Sensor #15230}
5 Wire; Wideband A/F; Check / Replace Interval: 100,000 Miles; Original Equipment Type - Upstream
$56.79 $0.00 $56.79

STANDARD MOTOR PRODUCTS Part # SG1089 {UPSTREAM SENSOR}
UPSTREAM SENSOR
$61.79 $0.00 $61.79

WALKER Part # 25024000 {Oxygen Sensor
Rear, From 04/01
4 wire, universal
Universal #22690AA540}
$64.79 $0.00 $64.79

AIRTEX Part # 5S4503
(Front)
$71.79 $0.00 $71.79

DENSO Part # 2344706
Rear; Downstream; Original Equipment Type
$78.79 $0.00 $78.79

BOSCH Part # 13469
4 Wire; Heated; Check / Replace Interval: 100,000 Miles; Original Equipment Type - Downstream
$94.79 $0.00 $94.79

STANDARD MOTOR PRODUCTS Part # SG1199
DOWNSTREAM SENSOR
$99.79 $0.00 $99.79

DENSO Part # 2349018 {Oxygen Sensor
Front
4 Wire, 14.96 Inch Wire
OE Type #22641AA00A}
$135.79 $0.00 $135.79

ACDELCO Part # 2133118 {#19107462}
SENSOR,HTD OXY(POSN 3) POST CONVERTER-4 WIRE
$138.79 $0.00 $138.79

AIRTEX Part # 5S4502
(Rear)
* Non-stock item--shipping delayed up to 2 business days
$102.79 $0.00 $102.79

ACDELCO Part # 2133896 {#19138031}
SENSOR,HTD OXY(POSN 1) IN EXH MANIFOLD/CROSSOVER-5 WIRE
* Non-stock item--shipping delayed up to 3 business days
$106.79 $0.00 $106.79

AIRTEX Part # 5S3922
(Front)
* Non-stock item--shipping delayed up to 2 business days
$215.99 $0.00 $215.99
 

· ITS TURBO TIME!
05 LGT limited
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3,647 Posts
The front one would be your A/F meter a.k.a. Front O2 sensor. Thats the Bosch part number 17018. The one at the end is the rear O2 sensor a.k.a. Cat. Effeciency meter and dreaded cause of the infamous P0420 code. i believe the Bosch number on the rear one is 13469.
 

· Registered
'06 LGT SWP
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344 Posts
Discussion Starter · #4 ·
The front one would be your A/F meter a.k.a. Front O2 sensor. Thats the Bosch part number 17018. The one at the end is the rear O2 sensor a.k.a. Cat. Effeciency meter and dreaded cause of the infamous P0420 code. i believe the Bosch number on the rear one is 13469.
Thanks for the info!! I was wondering, what happens when the rear O2 sensor goes out?? I know the front one you'll get some missfire, and some hesitation, but what does the rear one do, lets say i have a wire or 2 cut from it (runing rallitech O2 spacer and its too long, and the wires are rubbing gainst the underneath of the car) which will eventually cause the black and white wire to get cut. What does the rear O2 do, lets say theres a wire cut, what are the symptons the car will have?? Just want to be on the safe side.. before anything goes wrong...

JP
 

· Registered
'06 LGT SWP
Joined
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344 Posts
Discussion Starter · #5 ·
Thanks for the info!! I was wondering, what happens when the rear O2 sensor goes out?? I know the front one you'll get some missfire, and some hesitation, but what does the rear one do, lets say i have a wire or 2 cut from it (runing rallitech O2 spacer and its too long, and the wires are rubbing gainst the underneath of the car) which will eventually cause the black and white wire to get cut. What does the rear O2 do, lets say theres a wire cut, what are the symptons the car will have?? Just want to be on the safe side.. before anything goes wrong...

JP
And would anyone have a part # for the rear one? either OEM # or Bosch #??

JP
 

· 4 please, to go.
Ver 7 STi GC, elderly L
Joined
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4,680 Posts
rear O2 OEM part #: 22690AA640

front O2 (a/f sensor) OEM part #: 22791AA00A

the rear O2 is primarily used as a catalyst efficiency meter, although i've heard it's also used to verify values gathered by the primary a/f sensor. As far as symptoms of rear O2 failure you won't see nearly as severe drivability decrease as the front O2 but you will definitely see a CEL either P0420 or the one saying that the heater circuit is failing IIRC.
 

· Registered
'06 LGT SWP
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344 Posts
Discussion Starter · #7 ·
rear O2 OEM part #: 22690AA640

front O2 (a/f sensor) OEM part #: 22791AA00A

the rear O2 is primarily used as a catalyst efficiency meter, although i've heard it's also used to verify values gathered by the primary a/f sensor. As far as symptoms of rear O2 failure you won't see nearly as severe drivability decrease as the front O2 but you will definitely see a CEL either P0420 or the one saying that the heater circuit is failing IIRC.
Thanks!! Just making sure, soo its drivable, unlike the front O2, once it goes out, its a pain to drive the car... If anyone else has any symptoms if the rear O2 goes out, i would like to know!

Thanks
JP
 

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98 Posts
as far as i know the rear O2 sensor is mainly for emissions monitering and has very little to do with control, but the front O2 sensor is what your computer uses to adjust the air/fuel ratio. the rear is 4 wire and the front is 5 wire. the front i believe is a wideband which makes it more accurate in determining how much more or less fuel it needs to send vs the amout of intake of air.
 
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