Question about 2003 Chevrolet Impala

1 Answer

How do i determine which 02 sensor is defective? i've gotten a p0171 dtc and im not sure which sensor should be replaced

Posted by on

  • james bierman Sep 11, 2010

    po171 is not neccesarly a bad o2 sensor

×

1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 560 Answers

P0171 is not a defective sensor, it is the bank 1 (irrelivant) senor that has sensed a lean mixture... in other words too much oxygen in the exhaust.
This is usually a MAFS or MAP fault but it can be a leaking inlet gasket or simply a vac pipe disconnected.

Dony change an o2 sensor, they are working fine

Posted on Sep 11, 2010

1 Suggested Answer

6ya6ya
  • 2 Answers

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

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

2 Answers

I have a PO171 code on my 1999 Jeep grand cherakee larado can You tell me how to fix it, Thank You.


  • Dale, code P0171 fuel system too lean
  • Possible causes
  • change fuel filter first, if it has not been done recently
RESTRICTED FUEL SUPPLY LINE
FUEL PUMP INLET STRAINER PLUGGED
FUEL PUMP MODULE
O2 SENSOR
O2 SENSOR SIGNAL CIRCUIT SHORTED TO GROUND
O2 SENSOR HEATER OPERATION
TPS VOLTAGE GREATER THAN 0.92 VOLTS WITH THROTTLE CLOSED
TP SENSOR SWEEP
MAP SENSOR OPERATION
ECT SENSOR OPERATION
ENGINE MECHANICAL PROBLEM
FUEL FILTER/PRESSURE REGULATOR (HIGH)
PCM
Check the attached links,
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."

2000 Jeep Grand Cherokee p0171

Possible problems related to Code P0171 Jeep Garage Jeep Forum

P0171 System to Lean Bank 1

Code P0171

Mar 11, 2016 | Cars & Trucks

1 Answer

I have a 2001 Ford Focus p0 171 code check engine light is on


Hi there:
DTC P0171 - System to lean Bank 1

You might just have an air or a vacuum leak causing this code. This is pretty common. Be sure to check for vacuum leak such as hoses/lines leaking vacuum, intake manifold gaskets as well as the pcv hose behind the throttle body. I would check the PCV line from the passenger valve cover to the rear of the intake manifold. That line will collapse over time due to oil and age. It will create a vacuum leak. With the engine at idle, move the vacuum and PCV line and see if the idle changes and listen for a vacuum swushing sound. Both 02 sensors will not cause both of these codes.

Hope this helps.

Apr 09, 2013 | Cars & Trucks

1 Answer

Dtc fail code P0171 and then p2004


a po 171 is a bad 02 sensor

Mar 03, 2012 | Ford Cars & Trucks

1 Answer

Im throwing code p0171 bank 1 system too lean changed plugs fuel filter cleaned maf sensor swapped bank1 and bank 2 upstream 02 sensor to c if code red diff but it didnt and sprayed carb cleaner all over...


Your problem is the mass air flow sensor is bad theat code is miss leading a p0171 and p0174 are both miss leading replace the mass air flow sensor and clear the codes.

May 10, 2011 | GMC Sierra 1500 Cars & Trucks

2 Answers

Code p0171 system too lean bank 1


I could be wrong but that sounds like maybe an oxygen sensor (bank 1). Not sure what code i had on my car but the only bank 1 and bank 2 I heard of is the oxygen sensor but you can always go to autozone and they can check the code and tell you what it is.

Mar 03, 2011 | Buick Century Cars & Trucks

2 Answers

Engine light code p171 comes up. I recently changed the air flow sensor. Everything else is working fine. What can this be in a Toyota Corolla 2003?


DTC P0171 is set when fuel trim is driven rich beyond a certain value. Possible causes are:
1. Exhaust system leak.
2. Improper fuel pressure.
3. Fuel injector restricted.
4. Defective heated oxygen sensor No. 1.
5. Defective Manifold Absolute Pressure (MAP) sensor.
6. Defective Engine Coolant Temperature (ECT) sensor.

System Too Lean. This code will set when an air fuel ratio sensor (O2 sensor) gets lazy.

Also, check for a vacuum leak on that side.



Jan 26, 2011 | 2003 Toyota Corolla

1 Answer

I have a scion tc 05 with this code p171 . what does it mean?


DTC P0171 is set when fuel trim is driven rich beyond a certain value. Possible causes are:
1. Exhaust system leak.
2. Improper fuel pressure.
3. Fuel injector restricted.
4. Defective heated oxygen sensor No. 1.
5. Defective Manifold Absolute Pressure (MAP) sensor.
6. Defective Engine Coolant Temperature (ECT) sensor.
When the air fuel ratio feedback is stable after the engine is at operating temperature and the fuel trim has reached its limit of correction to the rich side. (2 trip logic).
Feedback from the HO 2 sensor influences short-term fuel trim and short-term fuel trim influences long trim fuel trim. Short-term values are temporary and not stored when the ignition key is turned off. Long-term values are stored in memory because they are part of the basic injection duration. Long term values affect injection duration in closed and open loop because they are used to calculate basic injection duration. It is important to remember that the actual fuel trim will be the opposite of the DTC. A system too lean, DTC P0171 will mean the ECM is making a + or rich correction.
read (and let me know)above data and Freeze Frame by using (example, generic) Scan Tool on # mode 2, etc.
Slowly accelerate the engine in the increments shown and record voltage,
grams/sec of MAF and SFT, LFT, Injection Pulse, Fuel Pressure, etc.
HTH,
Vehicle have MAF Sensor?

Jan 03, 2011 | 2001 Toyota Corolla

1 Answer

Emissions egr came up on the computer test i replace it now oxygen sensor are coming up its has 4


a defective EGR valve will at time effect 02 sensor functions. But even though you vehicle does have 4 02 sensor. The DTC (diagnostic trouble code) will indicate which 02 sensor is faulty. ask the tech who performed the test on your vehicle to tell you which sensor has malfunctioned. or get the dtc code from him then google the dtc for your vehicle and you will have the answer to your question

Mar 21, 2010 | Ford Windstar Cars & Trucks

1 Answer

Ford windstar check engine light comes on after stopping when starting to get moving again shows p0171 & p0174 codes why??


P0171 indicates a lean condition. The most common cause of this is a defective mass air flow sensor. Also check if any vacuum leaks. P0174 OBD-II Trouble Code


Technical Description

System Too Lean (Bank 2)


What does that mean?

Basically this means that an oxygen sensor in bank 2 detected a lean condition (too much oxygen in the exhaust.

Note: This DTC is very similar to P0171, and in fact your vehicle may show both codes at the same time.

-----------

Thanks.


Dec 17, 2009 | 2002 Ford Windstar Cargo

2 Answers

P0171 just change the mass air flow light came on


Hi,

Volvo's code - P0171 means: Long-term fuel trim, part load. Long-term fuel trim, idling.

You will need to refer to a workshop manual, to ascertain the correct inspection procedure.

Cheers,

Nov 05, 2009 | 2001 Volvo S60

Not finding what you are looking for?
2003 Chevrolet Impala Logo

722 people viewed this question

Ask a Question

Usually answered in minutes!

Top Chevrolet Experts

yadayada
yadayada

Level 3 Expert

75117 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22095 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

7772 Answers

Are you a Chevrolet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...