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Codes Read: PO135 and PO136 ring up (02 sensor related)...questions inside?

  • Thread starter Thread starter 5spd GT
  • Start date Start date Jul 6, 2006

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
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99
Arkansas
Jul 6, 2006
#1
  • Jul 6, 2006
  • #1
Got the codes read for why the service engine light is on...

It reads:

PO135
02 Sensor Heater
Bank 1, Sensor 1

PO136
02 Sensor
Bank 1, Sensor 2


Bank 1 is driver side right?

So does this mean I need to replace both sensors, front and back of the driver side?
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
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89
the people's republic of massachusetts
Jul 6, 2006
#2
  • Jul 6, 2006
  • #2
both of those codes are circuit faults for bank 1 ( passenger side)

p0135 is a 02 heater cicuit fault and p0136 is a circuit fault for the downstream sensor on bank 1

I would first inspect the sensors for damage and then the harness itself. Look for a pinch in the harness, most likely without looking at the diagram I would bet any harness damage would have to be near the firewall on the passenger side.
 

SunburstGoldGT

New Member
Dec 17, 2003
133
0
0
Blacksburg, VA
Jul 6, 2006
#3
  • Jul 6, 2006
  • #3
Also check fuse number 8 under the dash haha, i had the same codes plus 2 others and it was a simple fuse. Yellow 15 amp, its "engine controls", SVTTECH76 helped me with that one!
 

5spd GT

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Jul 15, 2006
#4
  • Jul 15, 2006
  • #4
Any places for the cheapest priced 02's?

I have a miss around the 2-2,400 rpm area under part throttle. I figure it is related to the 02's being out.

All the connections looked fine...
 

Mike97gt

it doe snot
Founding Member
Jan 26, 1999
10,633
7
89
the people's republic of massachusetts
Jul 15, 2006
#5
  • Jul 15, 2006
  • #5
5spd GT said:
Any places for the cheapest priced 02's?

I have a miss around the 2-2,400 rpm area under part throttle. I figure it is related to the 02's being out.

All the connections looked fine...
Click to expand...


Don't you think it's slightly odd that both passenger side 02 heater circuits are out at the same time. I find it highly unlikely that two sensors went out at the exact same time.

Before you buy new sensors I would check the wiring to the sensors.
 

5spd GT

"the 5.0 owns all"
Founding Member
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Jul 15, 2006
#6
  • Jul 15, 2006
  • #6
I checked the wires visually...nothing looked wrong.

I agree with you, I think it is odd...
 

5spd GT

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Feb 26, 2007
#7
  • Feb 26, 2007
  • #7
Okay, anybody got a place to get the o2 sensors cheaply?

My car is missing more and more now and the idle stumbles a bit at first start-up.
 

Tim2002GT

Founding Member
Apr 10, 2002
635
4
29
Tulsa, Oklahoma
Feb 26, 2007
#8
  • Feb 26, 2007
  • #8
Did you just recently swap out your midpipe? Mine did the same type of thing after I changed mine out. It turned out to be a bad exhaust leak on the drivers side header-midpipe flange.

If this isn't the case, then you could switch your two rear sensors just to see if you still get the same code
 

5spd GT

"the 5.0 owns all"
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Feb 26, 2007
#9
  • Feb 26, 2007
  • #9
Actually the car had been hit in the rear before I bought it. It has the stock H pipe...and it pops, sometimes pretty badly under WOT.

It has no mufflers on it (I assume because the stock catback was damaged, so to save money they didn't add it back on).

Thanks for the reply
 

LaserRed01GT

Banned
Oct 3, 2006
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Feb 26, 2007
#10
  • Feb 26, 2007
  • #10
It's possible that these codes are related, and it's possible that they are unrelated. The reason being is that the downstream(after cat) sensors are monitored for maximum and minumum voltage output whereas the upstream sensors are not. Both codes can be a result of a damaged wire, moisture in the connector, open circuit, or a short to power.

The most common causes of the P0135 that I have dealt with is just a bad sensor(heater) or moisture in the sensor connector.

The most common cause of the P0136 that I have dealth with is either an exhaust leak or bad sensor. But make sure that the Bank 1(passenger side) downstream sensor wiring harness is not chaffed and touching something.

Clear all codes, then move the Bank 2 sensors over to Bank1 and vice versa, and see if the codes follow the sensors, or if the codes still show a circuit problem on that Bank 1

Check your battery as well. Low system voltage can also trigger these types of codes.
 

5spd GT

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Feb 28, 2007
#11
  • Feb 28, 2007
  • #11
Thanks for the info, I'll do a last visual check and then start replacing.

Real quick, just for kicks, what is the size wrench I need to get the o2's off. Is it 7/8"
 

5spd GT

"the 5.0 owns all"
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Feb 28, 2007
#12
  • Feb 28, 2007
  • #12
Also, real quick, where is the cheapest place to get good o2 sensors?
 

5spd GT

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Mar 2, 2007
#13
  • Mar 2, 2007
  • #13
bump
 

LaserRed01GT

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Oct 3, 2006
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0
Clearwater, FL
Mar 2, 2007
#14
  • Mar 2, 2007
  • #14
5spd GT said:
Thanks for the info, I'll do a last visual check and then start replacing.

Real quick, just for kicks, what is the size wrench I need to get the o2's off. Is it 7/8"
Click to expand...

7/8". http://www.oxygensensorwholesale.com/
 
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