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Code PO155 on Chevy 2002 8.1L-replaced O2 sensor and codes still comes up?

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  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

  • 14 Answers

SOURCE: Check Engine Light - O2 Sensor - bank 1 running lean

you should have three oxygen sensors on your car, one for each bank of three cylinders; should be towards the Y pipe on each exhaust manifold. Additionally you should have one on the exhaust pipe before the cadilitic converter.

Posted on Nov 20, 2008

  • 66 Answers

SOURCE: O2 sensor problem

I have a 97 gmc sierra .This truck is the same as the chevy ok.Its a 350 5.7 liter 4x4 Z71.I took it to auto zone which was my first mistake.They put it the scanner and said bad O2 sensor.Ok so which one is it i said.They dont know.Well there four (4) O2 sensors in this truck i hope you know that.I had to replace all four of them before i had to take it to a real shop.It seems the fuel pump i replaced a week earlier with an auto zone fuel pump was bad.Ive changed my feul pump 4 times now and have 235000 miles on still running.You need to get your fuel pressure checked.It should be 65 psi to start it and 55 psi to run it.If the pressures are good it could be a different O2 sensor or maybe the mass air flow senor.My last option would be the fuel pressure regulator because it seems to be a waste of time and money.I would get that fuel pressue checked first.Good luck.

Posted on Nov 25, 2008

  • 71 Answers

SOURCE: Problem code P0133 ("O2 Circuit slow response")

yes i would recommend replacing the o2 sensor, 9 times out of 10 it will correct the problem and they usually aren't too expensive for the saturn's

Posted on Nov 27, 2008

  • 181 Answers

SOURCE: error code P0135 O2 sensor heater circuit

It is the o2 sensor itself replace 02 sensor. Keep in mind you have four of them. the computer will tell you which one has the fault example. bank 1 sensor 2 If I can help anymore please repost with engine size I will be happy to help DRIVE SAFE TIM

Posted on Feb 19, 2010

  • 17970 Answers


A code P0155 may mean that one or more of the following has happened:
* O2 Heater element resistance is high
* Internal short or open in the heater element
* O2 heater circuit wiring high resistance
* open or short to ground in the wiring harness

Possible Solutions:
* Repair short or open or high resistance in wiring harness or harness connectors
* Replace oxygen sensor (cannot repair open or short that occurs internally to sensor)

Oxygen sensors are always numbered like this:
Bank 1 sensor 1
Bank 2 sensor 1
Bank 1 sensor 2
Bank 2 sensor 2

Some manufacturers use a kind of shorthand that reads different, but means the same thing:
Sensor 1/1 or O2s 1/1
Sensor 2/1 or O2s 2/1
Sensor 1/2 or O2s 1/2
Sensor 2/2 or O2s 2/2

Bank 1 is always the side of the engine where cylinder number 1 is located and, of coarse, Bank 2 is the opposite side.
On a 4 cylinder engine, there is only 1 bank and it is always referred to as Bank 1.

Sensor 1 is always the upstream sensor (The one located BEFORE the catalytic converter)
Sensor 2 is always the downstream sensor (the one that is located AFTER the catalytic converter.

Hope helps (remember to rate this).

Posted on Oct 02, 2010

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2 Answers

What do po155 mean?

Assuming you mean p0155 obd code is an o2 sensor heater circuit fault this could be the heater in the o2 sensor itself check for continuity or it could be a short in the wiring harness. Clear the code and see if it comes back! If you have done more than 100k miles in your car the o2 sensor is most likely due for replacement. best to confirm the fault first

Apr 14, 2014 | 1999 Chevrolet Astro

1 Answer

97 suburban runs rough, codes po141,po157,po300,po155

Well, code 141 is for a problem with the heater circuit for O2 sensor bank one sensor two which is after the catalytic converter.
Code 157 is for the same issue but with bank two sensor two, and 155 is for bank two sensor one. I would look at the wiring for those O2 sensors first. It is very rare for more than one O2 sensor to fail at any given time.
Code 300 is for a random miss which may be tough to track down.

Feb 06, 2014 | Chevrolet Cars & Trucks

1 Answer

Trouble codes for 2003 Chevy Blazer

Code 155 is for a problem with the heater circuit in the O2 sensor for bank two. Bank two is on the side with cylinder number two.
Usually the sensor is faulty, but the heater circuit would need to be checked to be sure. The sensor has a built-in heater to get it hot quickly after starting the engine.

Jul 10, 2013 | Cars & Trucks

1 Answer

Codes po122 po155 po135 po102

code po122 is for your throttle position sensor. po155 is for your down stream o2 senor .po135 is for your bank 1 sensor 1 o2 sensor. po102 is for your maf sensor

Dec 19, 2012 | 2000 Ford Expedition

1 Answer

Why the codes po125 & po135 &po155 keep coming back?

Hi there:

DTC P0125 - Insufficient Coolant Temperature For Closed Loop Fuel Control

The simplest thing to do is to reset the code and see if it comes back.
If the code comes back, the problem is likely going to be the result of the above causes (faulty thermostat, faulty ECT sensor, or a low coolant level).

DTC P0135 - Oxygen O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)
DTC P0155 - 02 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1)

A code P0135 and P0155 may mean that one or more of the following has happened:

  • O2 Heater element resistance is high
  • Internal short or open in the heater element
  • O2 heater circuit wiring high resistance
  • open or short to ground in the wiring harness

In order to solve just...
  • Repair short or open or high resistance in wiring harness or harness connectors
  • Replace oxygen sensor (cannot repair open or short that occurs internally to sensor)

  • Hopoe this helps.

    Aug 28, 2012 | 1999 Toyota Sienna

    1 Answer

    2003 GMC Sonoma 81000 miles 4.3l engine PO155 error code. I cleared it, but it came back 4 days later while driving around town. Should I replace the sensor?


    Aug 19, 2011 | 2003 GMC Sonoma Extended Cab

    1 Answer

    What do codes PO155 and PO155(PD) mean?

    P0155 code for Isuzu 2002 Axium
    The Oxygen sensor heater (comes as one unit with O2 sensor.)

    Apr 07, 2010 | 2002 Isuzu Axiom

    1 Answer

    PO155 code for 1998 chevy camaro V6 Where is the sensor bank located and how many are there for this car?

    they are you're o2 sensors and they are located on the exhaust pipe.there are 3 or 4 on it.

    Jan 13, 2010 | 1998 Chevrolet Camaro

    1 Answer

    99 chevy blazer LS is popping out the tail pipe & carb code came up as po155

    It is not a carb code as your vehicle has not carburetor. It is an OBD2 ECU code. What is means is that you have an O2 sensor heater circuit malfunction (Bank 2 Sensor 1). In your case I would recommend you inspect all the wiring going to that O2 sensor. If you find no problems then I suggest you replace the O2 sensor. The sensor to replace is on the passenger side, the sensor closest to the engine. This will more than likely fix your problem. After replacing the sensor reset the Check Engine Light. If the problem comes back then seek professional help and do not replace any other parts.

    Dec 20, 2009 | 1999 Chevrolet Blazer

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