Question about Dodge Durango

1 Answer

99 dodge durango keeps throwing the troublecode p0171 ( o2 sensor bank 1 too lean) It has new o2s and a new pcm Any Ideas?

Posted by on

  • 3 more comments 
  • billyvegas70 Feb 04, 2010

    Im only getting about 10 or 11 on my vacuum gauge... I didnt know if that was right because im in utah at a higher elevation. When you start the car it runs fine. Once it seems to hit closed loop it runs like garbage. There are new spark plugs and wires. Now answer me this.... With my Diagnostic tool plugged in before i put in a new pcm it would say i was getting no voltage from that front o2. so when it thought it was running lean it was running very rich. There is a signal coming from the sensor all the way up to the pcm. It seems like this is a huge problem with dodges not just the 5.9 even 5.2 and the 4.7. I just dont understand how this can keep happening. I have sprayed ether around the engine looking for vacuum leaks and it didnt change anything. I also did a new gasket kit on the intake manifold.

  • billyvegas70 Feb 04, 2010

    There is good compression 149-151 across the bored and there isnt any restrictions in the exhaust cause its leaving black marks where i leave it idle

  • billyvegas70 Feb 04, 2010

    Ill put it on the modis at work today and let you know... Im gonna check all these other parts... But thank you i will be in touch

  • billyvegas70 Feb 04, 2010

    I went to look at that actually but i think thats the 4.7 theres really no wires by mine but i shall look... I only have an o2 at they Y its not a california emissions vechile so bank 1 is actually pre cat....

  • billyvegas70 Feb 05, 2010

    You have really been a big help but this wasnt my car it was my Chiefs Truck that he wants to sell ( im in the Air Force) I told him to take it to dodge cause i cant keep working on this thing... It seems to happen to a ton of people and dodge i dont think even knows how to fix it but we shall see...

    Im gonna keep your email cause im always working on cars and its always nice to have a second opinion.



1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.


    An expert whose answer got voted for 500 times.

  • Master
  • 1,168 Answers

Hello Billy.
If you are getting a lean code with new sensors you will have to find out why it is going lean.
Several things to check.
Has to be 13 inches of vacuum at idle minimum.
Timing must be in specification.
Good engine compression.
No exhaust restrictions or leaks.
The PCV system must be working properly.
Plugged up fuel injectors or poor fuel.
A bad MAP sensor.
A leaking brake vacuum booster or intake manifold vacuum leak.
All these items can create the lean sensor code.
If you need more info let me know.


Posted on Feb 04, 2010

  • 5 more comments 
  • FUBAR Feb 04, 2010

    Hello again Billy.
    Just because it is coming out the end of the pipe doesn't mean there isn't a restriction. A restriction can mean partially plugged catalytic converter or muffler. As your engine speed increases that is when it comes into the equation as more flow is happening.
    It probably isn't that anyway but you asked for ideas and I did give them to you.
    What about the rest of the suggestions, were they looked into recently?
    Has it been tuned up in the recent months?
    Does the truck lack power?
    What about exhaust leaks?

  • FUBAR Feb 04, 2010

    Im only getting about 10 or 11 on my vacuum gauge... I didnt know if
    that was right because im in utah at a higher elevation. When you start
    the car it runs fine. Once it seems to hit closed loop it runs like
    garbage. There are new spark plugs and wires. Now answer me this....
    With my Diagnostic tool plugged in before i put in a new pcm it would
    say i was getting no voltage from that front o2. so when it thought it
    was running lean it was running very rich. There is a signal coming
    from the sensor all the way up to the pcm. It seems like this is a huge
    problem with dodges not just the 5.9 even 5.2 and the 4.7. I just dont
    understand how this can keep happening. I have sprayed ether around the
    engine looking for vacuum leaks and it didnt change anything. I also
    did a new gasket kit on the intake manifold.

    Sorry Billy, missed your first reply.
    Vacuum is low, even at elevation. Could be because of the poor running too.
    What kind of voltage is coming from the sensor on bank 1 when warmed up?
    Is it possible you have a defective one ?
    The black you mentioned coming out the pipe is indicating too much fuel. But this could be caused by bank 2 running too rich by bank one adding fuel.
    Common for the dodge not to send a voltage signal when at idle, I think because of not enough heat to activate them.
    What about the egr valve ? Is it sticking?

  • FUBAR Feb 04, 2010

    I'd sure like to know what your MAP sensor is reading.

  • FUBAR Feb 04, 2010

    Ok Bill.
    Keep me informed.
    We will get it fixed.

  • FUBAR Feb 04, 2010

    Hello again Bill.
    Doing some research I came across several instances of power steering fluid leaking into the O2 sensor harness and shorting the signal. Apparently a real problem with leaking power steering pressure switches and it tracks down to the connector.
    Have a look for signs of fluid at the connector.

  • FUBAR Feb 04, 2010

    OK Bill, just looking for all the possibilities. I wasn't sure what engine you had.

  • FUBAR Feb 05, 2010

    OK Billy.
    Hope you can get it going.
    Sorry we couldn't keep at it.
    Hate to lose out on a proper fix.
    Thanks for sticking with me.
    Any time I can help let me know.



1 Suggested Answer

  • 2 Answers

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

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.

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%


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



Related Questions:

1 Answer

Hi i have a 2002 ford ranger and it has teas codes P0446 P0135 P0141 P2195 P0403 P0171

P0446: EVAP System Vent Control Circuit

P0135: O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1
P0135 Ford O2 Sensor Heater Circuit Malfunction Bank 1 Sensor 1

P0141: O2 Heater Circuit Bank 1 Sensor 2
P0141 Ford O2 Heater Circuit Bank 1 Sensor 2

P2195: Oxygen Sensor Signal Biased/Stuck Lean - Bank 1 Sensor 1

P0403:Exhaust Gas Recirculation Control Circuit

P0171: Fuel Injection System Too Lean Bank 1

Nov 15, 2016 | 2002 Ford Ranger

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
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

2 Answers

What are the probable causes of DTC P0171?

P0171 refers to System to lean on bank #1

Aug 07, 2015 | Dodge Cars & Trucks

1 Answer

The check engine comes on but I dont lose power the code it is showing is sid 152.does anyone know what it is.

some codes dont cause power loss or may not even notice anything wrong but a check engine light a p0152 code means following answer courtesy of === P0152 O2 Sensor (High Voltage) OBD-II Trouble Code Technical Description Article by Dale Dale Toalston ASE Certified Technician 02 Sensor Circuit High Voltage (Bank 2 Sensor 1) What does that mean? The o2 (oxygen) sensors basically measure oxygen content in the exhaust. The PCM (powertrain control module) then uses this information to regulate fuel injector pulse. The o2 sensors are very important to proper operation of the engine. Problems with them can cause the PCM to add or take away too much fuel based on the faulty o2 sensor voltage. A P0152 code refers to the Bank 2, sensor 1, o2 sensor. (Bank 1 would contain cylinder 1 and bank 2 is the opposite bank. Bank 2 doesn't necessarily contain cylinder 2.) "Bank 2" refers to the side of the exhaust that DOES NOT contain cylinder number 1 and "Sensor 1" indicates that it is the pre-cat sensor, or forward(first) sensor on that bank. It is a four wire sensor. The PCM supplies a ground circuit and a reference voltage of about .5 volts on another circuit. Also for the o2 heater there is a battery voltage supply wire and another ground circuit for that. The o2 sensor heater allows the o2 sensor to warm up faster, thus achieving closed loop in less time than it would normally take for the exhaust to warm the sensor up to operating temperature. The O2 sensor varies the supplied reference voltage based on oxygen content in the exhaust. It is capable of varying from .1 to .9 volts, .1 indicating lean exhaust and .9 indicating rich exhaust. NOTE: A condensed explanation of fuel trims: If the o2 sensor indicates that the oxygen voltage reading is .9 volts or high, the PCM interprets this as a rich condition in the exhaust and as a result decreases the amount of fuel entering the engine by shortening injector "on time". The STFT (short term fuel trims) would reflect this change. The opposite would occur when the PCM sees a lean condition. The PCM would add fuel which would be indicated by a single digit positive STFT reading. On a normal engine the front o2 sensors switch rapidly back and forth two or three times per second and the STFT would shift positive and negative single digits to add and remove fuel to compensate at a similar rate. This little "dance" goes on to keep the air/fuel ratio at it's optimal level. Short term fuel trims or STFT reflect immediate changes in fuel injector "on-time" while long term fuel trims or LTFT reflect changes in fuel over a longer period of time. If your STFT or LTFT readings are in the positive double digits (ten or above), this indicates the fuel system has been adding an abnormal amount of fuel than is necessary to keep the proper air/fuel ratio. It may be overcompentsating for a vacuum leak or a stuck lean o2 sensor, etc. The opposite would be true if the fuel trim readings are in the negative double digits. It would indicate that the fuel system has been taking away excessive amounts of fuel, perhaps to compensate for leaking injectors or a stuck rich o2 sensor, etc. So when experiencing o2 related issues, reading your fuel trims can indicate what the PCM has been doing over the long term and short term with regard to fuel. This code indicates that the o2 sensor was stuck too high or in the rich position. The PCM monitors this voltage and if it determines that the voltage is too high out of range for too long, P0152 may set. Symptoms Symptoms may include: MIL (Malfunction Indicator Lamp) illumination Engine may run very rough Engine may be running lean or rich depending on if the o2 sensor is reading correctly or incorrectly Lack of power Increased fuel consumption Causes Potential causes of an P0152 code include: Bad bank 2, 1 o2 sensor incorrectly reading rich condition Engine running rich and o2 sensor Correctly reading rich condition Signal shorted to voltage in harness Wiring harness damage/melted due to contact with exhaust components Vacuum leak (make have lean codes (P0171, P0174) present with it) Leaking injectors Bad fuel pressure regulator Bad PCM Possible Solutions If you have any lean or rich codes associated with this code, focus on fixing these first because these can cause the o2 sensor voltage readings to appear to be faulty when they are in fact only reading correctly. So, with the engine running at operating temperature, use a scan tool to observe the Bank 2,1 o2 sensor voltage reading. Is it high? If so, look at the long term and short term fuel trim readings. The fuel trims are affected by the o2 sensors as noted above. If the LTFT reading for that bank is indicating negative double digits (PCM trying to take away fuel to compensate for problem) try inducing a vacuum leak to see if the sensor voltage then goes lean and the fuel trims increase. If the o2 sensor responds, suspect a problem with the engine, not the sensor. There may be other engine codes to help you. If the o2 sensor reading remains high (0.9 volts or above) and won't respond then shut off engine. With KOEO (Key on engine off) disconnect the o2 sensor and look for signs of corrosion or water intrustion. Repair as necessary. The voltage reading should now be about 0.5 volts. If so, replace the o2 sensor, it's shorted internally. If after unplugging the o2 sensor the voltage reading on the scan tool doesn't change, then suspect wiring problems. Inspect the harness and look for any melted wires or anywhere that the o2 sensor harness is making contact with the exhaust components. If you are unsure, you can check for continuity of all four wires between the sensor and the PCM with an ohmmeter. Any resistance at all indicates a problem. Repair as necessary.

Read more at:
Copyright ©

Jul 28, 2015 | Cars & Trucks

1 Answer

What is p0171 p0174?

P0171 Fuel trim bank one condition Lean (If bank one and two codes set together suspect fuel pressure or MAF sensor. Or O2 sensor defective
P0174Fuel trim bank two condition Lean (same as above or Failed H02S21 Heated O2 sensor Bank 2 sensor 1)

May 11, 2014 | 2000 Jeep Grand Cherokee

1 Answer

2006 kia spectra oem code p2626, p0171, p0170??

P2626 O2 Sensor Pumping Current Trim Circuit/Open
P0171 System too Lean (Bank 1)
P0170 Fuel Trim Malfunction - Bank 1.

Try changing the fuel filter first. Then you will have to clear the code with a jumper.

Check here:

Oct 28, 2013 | 2007 Kia Spectra LX Sedan

1 Answer


P0171....System too Lean (Bank 1)

suggest you check O2 sensors on bank 1 ,their are two sensors one before and one after the cat ,think it may be the rear one playing up ,use a automotive meter to test them .

Mar 31, 2011 | 2000 Dodge Durango

1 Answer

1996 dodge dakota black smoke, engine running horrible getting P0171 code?

It sounds like your engine is running very rich yet the computer thinks it's lean. P0171 is a lean code for bank 1 (the side of the engine with cylinder #1) Pretty much the only causes could be a large exhaust leak, bad o2 sensor or bad computer. Is the p0171 the only code?

Jul 31, 2010 | 1996 Dodge Dakota

1 Answer

P0137 p0171 p0174

P0137 o2 circuit low voltage bank 1 sensor 2 --o2 sensor after the cat converter -check for faulty o2 sensor -short or open circuit exhaust leak near sensor or plugged cat converter ----P0171 and P0174 -system too lean bank 1--and system too lean bank 2 they are usually from the same problem which can be caused from the o2 problem but check ur maf sensor connections and or clean if necessary[carb cleaner] vacuum leak downstream from maf sensor also inspect pcv lines

Feb 16, 2010 | 2003 Chevrolet Silverado 1500

3 Answers

Codes 1133-0131-0171-0300

p1133 - o2 sensor, Insufficiant Switching, Bank 1 Sensor 1.
p0131 - o2 sensor circuit, low voltage, bank 1 sensor 1
p0171 - Lean condition, Bank 1
p0300 - Random Misfire

I would be looking at the front passenger side oxygen sensor for issues. It may be bad, it may not be plugged in, bad wiring at harness.

The random misfire may be symptomatic of the o2 sensor problem.

Mar 17, 2009 | 2002 Chevrolet Silverado 1500

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

91 people viewed this question

Ask a Question

Usually answered in minutes!

Top Dodge Experts


Level 3 Expert

75817 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22156 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8180 Answers

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

Answer questions

Manuals & User Guides