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P0171 Diagnostic Trouble Code Discussion for December 2006

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
1999 Lexus RX300 3.0L Excessive Emissions, Surge, MIL Lamp on VIN: JT6HF10V0X
P0171: system too lean bank 1. ... with a very intermittent problem. Code P0171 sets and we replaced the MAF sensor last week with an OEM Toyota part from worldpac. We previously couldn't get the vehicle to act up. Previous freeze-frame data showed long-term fuel trims very high (over 50%, ...
December 04, 2006
1999 Ford Windstar LX 3.8L Excessive Emissions, MIL Lamp on VIN: 2FMZA5143X
P0171: Too lean bank one. ... drivability issues, only the two codes P0171 & P0174 too lean bank one and two, along with some messed up fuel trims. I work on many of these vans and have had great success repairing these codes in the past by performing the usual r...
December 07, 2006
1998 Oldsmobile Aurora 4.0L MIL Lamp on VIN: 1G3GR62C0W
P0171: Fuel Trim System Lean (Bank 1). ... this. Owners complaint is CE lite, runs fine. Codes P0171 and P0174. I can spray carb cleaner at loud "whistling" trap door at front of intake manifold and bring LTFT from + 37% down to normal, or even flood out engi...
December 10, 2006
1998 Ford Ranger Splash 4.0L MIL Lamp on VIN: 1FTYR14X7W
P0171: System to lean bank 1. ... Ranger... setting codes p0171 and p0174. Apon start up, my long term fuel trim values are between 30-40%, while check for vacuum leaks, I found the upper intake plenum gaskets leaking, tube from EGR valve to intake seal leaking,...
December 11, 2006
1996 Ford E-250 Econoline 4.9L MIL Lamp on VIN: 1FTFS24Y3T
P0171: lean air/fuel ratio. ... codes p0171/p0174. fuel pump was replaced last month (it failed) mass air flow sensor was replaced same day - it had 151hz reading. normal in this area is 156hz. battery was disconnected and cables touched together to reset KAM. all vacuum hoses including ...
December 12, 2006
2001 Ford Escort SE 2.0L Cuts out, Stall VIN: 3FAFP13P41
P0171: bank one system lean. This '01 escort stalls at idle and runs rough. Runs good on the road. Tried a new mass air flow sensor(MAF), has a new O2 sensor. No vacuum leaks found, but MAF only reads .30 volts when it idles. Spec says it should be .7 to 1.0 volts. Which makes me think Im...
December 12, 2006
1999 Ford Windstar LX 3.8L Poor Idle Quality, MIL Lamp on VIN: 2FMZA5144X
P0171: bank 2 system too lean. hello ford techs,have this windstar with an intermittent idle problem,retrieve codes 171 & 174 for lean condition, thought it was easy enuff,check for vacuum leaks-none found even smoke tested & tested old fashion way,so you think its the air box (maf)...
December 13, 2006
1999 Ford Windstar SEL 3.8L Misfire, MIL Lamp on VIN: 2FMZA5349X
P0171: lean bank 1. This van had the typical lean codes and oil swelled fuel regulator hose. I performed the repairs per the TSB with the new valve cover, upper intake isolator bolts and gaskets. The problem is I still have is a misfire on cylinder 3. It is pretty regular on acce...
December 14, 2006
1997 Pontiac Bonneville SE 3.8L Hesitation, Misfire, MIL Lamp on VIN: 1G2HZK7VH2
P0171: Fuel System Lean. Here a good one guys...Car came in surging idle and misfire and lean code. Car has new plugs, wires, fuel filter, pcv,and ignition module. Intake Of Course... was leaking around the egr tube surprise... Now the car is only misfiring on the front 3 cylinders. F...
December 15, 2006
2002 Volvo S60 2.4L Poor Idle Quality, Hesitation, Surge, MIL Lamp on, NOISE VIN: YV1RS61R12
P0171: fuel system lean. ... a loud space ship type noise under hood.scan test found p0171(system lean code),freeze frame had fuel trims at st +15% lt +24%.noise could be heard coming from under timing cover very loud screaming type sound(like could be made by deflating a balloon or b...
December 15, 2006
2000 Ford Focus LX 2.0L MIL Lamp on VIN: 1FAFP33P8Y
P0171: sys. lean bank 1. Initially pulled p0171 from vehicle w/ok drivability except idle dip occasionally when slowing, and little rough @ idle. Found Long term FT at +32% @ idle and off-idle within 10%. (seems like clear cut vac. leak !!??) Also found in data that eng temp low after...
December 17, 2006
2000 Toyota Corolla VE 1.8L Excessive Emissions, MIL Lamp on VIN: 2T1BR12E8Y
P0171: Fuel System Too Lean (Bank 1). I have this corolla that runs lean I have tryed every thing 02 sensor does not switch at idle I have tryed new 02 from toy new air flow meter ran toyota injector cleaner no diff.no vac leaks no exhaust leaks and no other codes .Could the vvt screw up and not s...
December 18, 2006
2002 Volvo S60 2.4L Poor Idle Quality, Hesitation, Surge, MIL Lamp on, NOISE VIN: YV1RS61R12
P0171: fuel system lean. ... a loud space ship type noise under hood.scan test found p0171(system lean code),freeze frame had fuel trims at st +15% lt +24%.noise could be heard coming from under timing cover very loud screaming type sound(like could be made by deflating a balloon or b...
December 18, 2006
1997 Mazda B4000 4.0L MIL Lamp on VIN: 4F4DR17X8V
P0171: Adaptive Fuel Trim Too Lean (Bank 1). Help Mazda/Ford techs,I'm a GM fuel/elelctrical guy that rarely works on these.I have a MT2500 and had to program it to read as Ford to get into this system.Seems to communicate just fine.Looks all like a Ford truck to me.Have these lean codes,but truck runs g...
December 20, 2006
2000 Nissan Maxima GLE 3.0L Excessive Emissions, Cuts out, Stall VIN: JN1CA31A9Y
P0171: Fuel Trim Lean (Bank 1). after o2 sensors test fuel pressure ok,test maf 1.6v at idle and rises as expected with threottle opening.no drop outs or glithches.will be idling ok then just stall out. any ideas would be appeciated
December 20, 2006
2001 Nissan Maxima GLE 3.0L low power VIN: JN1CA31A91
P0171: Fuel Trim Lean (Bank 1). ... external fuel to intake, it recovers, if I pinch return line the power returns. I put a Delphi pump in with no change. Replace fuel press. regulator, still no change. p0171 was only code and I cannot get a running pressure because of Nissan special tool ne...
December 22, 2006
2000 Plymouth Neon High Line 2.0L MIL Lamp on VIN: 1P3ES46C9Y
P0171: Fuel System Lean (Bank 1). car fail emission for p0171 no leak car runs great any help wellcome thanks
December 22, 2006
1998 Ford Contour SVT 2.5L MIL Lamp on VIN: 1FALP68GXW
P0171: bank 1 lean. We smoke tested vehicle, no leaks found, except from breather hole at idle air control valve, (not sure if this is normal, have that used smoke machine too often on a ford) Long trim on bank 1 and bank2 max out at 25%, There is no driviablity problem except th...
December 23, 2006
2001 Cadillac Catera 3.0L Misfire, MIL Lamp on VIN: WO6VR54R61
P0171: Fuel Trim System Lean (Bank 1). this vehicle high long term fueltrim. when getting to 23 percent the check engine lite comes on. we cleaned the mass air flow, checked for vac leaks, checked fuel pressure which is 42psi, and replaced a plugged fuel filter. after driving several time the fuel ...
December 27, 2006
2003 Ford E-250 4.2L Poor Fuel Economy, MIL Lamp on VIN: 1FTNS24253
P0171: system too lean b1. ... above the van was good for aprox. 350 miles. Then the MIL came back on with all the same codes excluding the p0300 misfire code. I performed this TSB with care, properly tourging bolts in sequence and cleaning sufaces perfect...
December 29, 2006
1996 Pontiac Grand Am SE 2.4L MIL Lamp on VIN: 1G2NE52T5T
P0171: Fuel System Lean. Hello, First let me apologize for the limited info. I am trying to help a very poor friend get her car fixed and I am in a different city. Ever been there? Also, I am a big rig tech and I only work on cars (mostly Fords) on a limited basis. My question is thi...
December 30, 2006
1996 Pontiac Grand Am SE 2.4L MIL Lamp on VIN: 1G2NE52T5T
P0171: Fuel System Lean. Hello, First let me apologize for the limited info. I am trying to help a very poor friend get her car fixed and I am in a different city. Ever been there? Also, I am a big rig tech and I only work on cars (mostly Fords) on a limited basis. My question is thi...
December 31, 2006
2000 Toyota Tacoma DLX 2.4L MIL Lamp on
P0171: Fuel System Too Lean (Bank 1). ... found dtc p0171 system lean and p0420 cat. problem. we replace oem maf sensor and oem cat.car came back a week later with dtc P0171 so i start checking everything that cause lean problem. vaccum leak, exhaust leak, comprison, fuel pressur, fuel vol. intake...
December 31, 2006
1999 Lexus RX300 3.0L Excessive Emissions, Surge, MIL Lamp on VIN: JT6HF10V0X
P0171: system too lean bank 1. ... with a very intermittent problem. Code P0171 sets and we replaced the MAF sensor last week with an OEM Toyota part from worldpac. We previously couldn't get the vehicle to act up. Previous freeze-frame data showed long-term fuel trims very high (over 50%, ...
December 04, 2006
1999 Ford Windstar LX 3.8L Excessive Emissions, MIL Lamp on VIN: 2FMZA5143X
P0171: Too lean bank one. ... drivability issues, only the two codes P0171 & P0174 too lean bank one and two, along with some messed up fuel trims. I work on many of these vans and have had great success repairing these codes in the past by performing the usual r...
December 07, 2006
1998 Oldsmobile Aurora 4.0L MIL Lamp on VIN: 1G3GR62C0W
P0171: Fuel Trim System Lean (Bank 1). ... this. Owners complaint is CE lite, runs fine. Codes P0171 and P0174. I can spray carb cleaner at loud "whistling" trap door at front of intake manifold and bring LTFT from + 37% down to normal, or even flood out engi...
December 10, 2006
1998 Ford Ranger Splash 4.0L MIL Lamp on VIN: 1FTYR14X7W
P0171: System to lean bank 1. ... Ranger... setting codes p0171 and p0174. Apon start up, my long term fuel trim values are between 30-40%, while check for vacuum leaks, I found the upper intake plenum gaskets leaking, tube from EGR valve to intake seal leaking,...
December 11, 2006
1996 Ford E-250 Econoline 4.9L MIL Lamp on VIN: 1FTFS24Y3T
P0171: lean air/fuel ratio. ... codes p0171/p0174. fuel pump was replaced last month (it failed) mass air flow sensor was replaced same day - it had 151hz reading. normal in this area is 156hz. battery was disconnected and cables touched together to reset KAM. all vacuum hoses including ...
December 12, 2006
2001 Ford Escort SE 2.0L Cuts out, Stall VIN: 3FAFP13P41
P0171: bank one system lean. This '01 escort stalls at idle and runs rough. Runs good on the road. Tried a new mass air flow sensor(MAF), has a new O2 sensor. No vacuum leaks found, but MAF only reads .30 volts when it idles. Spec says it should be .7 to 1.0 volts. Which makes me think Im...
December 12, 2006
1999 Ford Windstar LX 3.8L Poor Idle Quality, MIL Lamp on VIN: 2FMZA5144X
P0171: bank 2 system too lean. hello ford techs,have this windstar with an intermittent idle problem,retrieve codes 171 & 174 for lean condition, thought it was easy enuff,check for vacuum leaks-none found even smoke tested & tested old fashion way,so you think its the air box (maf)...
December 13, 2006
1999 Ford Windstar SEL 3.8L Misfire, MIL Lamp on VIN: 2FMZA5349X
P0171: lean bank 1. This van had the typical lean codes and oil swelled fuel regulator hose. I performed the repairs per the TSB with the new valve cover, upper intake isolator bolts and gaskets. The problem is I still have is a misfire on cylinder 3. It is pretty regular on acce...
December 14, 2006
1997 Pontiac Bonneville SE 3.8L Hesitation, Misfire, MIL Lamp on VIN: 1G2HZK7VH2
P0171: Fuel System Lean. Here a good one guys...Car came in surging idle and misfire and lean code. Car has new plugs, wires, fuel filter, pcv,and ignition module. Intake Of Course... was leaking around the egr tube surprise... Now the car is only misfiring on the front 3 cylinders. F...
December 15, 2006
2002 Volvo S60 2.4L Poor Idle Quality, Hesitation, Surge, MIL Lamp on, NOISE VIN: YV1RS61R12
P0171: fuel system lean. ... a loud space ship type noise under hood.scan test found p0171(system lean code),freeze frame had fuel trims at st +15% lt +24%.noise could be heard coming from under timing cover very loud screaming type sound(like could be made by deflating a balloon or b...
December 15, 2006
2000 Ford Focus LX 2.0L MIL Lamp on VIN: 1FAFP33P8Y
P0171: sys. lean bank 1. Initially pulled p0171 from vehicle w/ok drivability except idle dip occasionally when slowing, and little rough @ idle. Found Long term FT at +32% @ idle and off-idle within 10%. (seems like clear cut vac. leak !!??) Also found in data that eng temp low after...
December 17, 2006
2000 Toyota Corolla VE 1.8L Excessive Emissions, MIL Lamp on VIN: 2T1BR12E8Y
P0171: Fuel System Too Lean (Bank 1). I have this corolla that runs lean I have tryed every thing 02 sensor does not switch at idle I have tryed new 02 from toy new air flow meter ran toyota injector cleaner no diff.no vac leaks no exhaust leaks and no other codes .Could the vvt screw up and not s...
December 18, 2006
2002 Volvo S60 2.4L Poor Idle Quality, Hesitation, Surge, MIL Lamp on, NOISE VIN: YV1RS61R12
P0171: fuel system lean. ... a loud space ship type noise under hood.scan test found p0171(system lean code),freeze frame had fuel trims at st +15% lt +24%.noise could be heard coming from under timing cover very loud screaming type sound(like could be made by deflating a balloon or b...
December 18, 2006
1997 Mazda B4000 4.0L MIL Lamp on VIN: 4F4DR17X8V
P0171: Adaptive Fuel Trim Too Lean (Bank 1). Help Mazda/Ford techs,I'm a GM fuel/elelctrical guy that rarely works on these.I have a MT2500 and had to program it to read as Ford to get into this system.Seems to communicate just fine.Looks all like a Ford truck to me.Have these lean codes,but truck runs g...
December 20, 2006
2000 Nissan Maxima GLE 3.0L Excessive Emissions, Cuts out, Stall VIN: JN1CA31A9Y
P0171: Fuel Trim Lean (Bank 1). after o2 sensors test fuel pressure ok,test maf 1.6v at idle and rises as expected with threottle opening.no drop outs or glithches.will be idling ok then just stall out. any ideas would be appeciated
December 20, 2006
2001 Nissan Maxima GLE 3.0L low power VIN: JN1CA31A91
P0171: Fuel Trim Lean (Bank 1). ... external fuel to intake, it recovers, if I pinch return line the power returns. I put a Delphi pump in with no change. Replace fuel press. regulator, still no change. p0171 was only code and I cannot get a running pressure because of Nissan special tool ne...
December 22, 2006
2000 Plymouth Neon High Line 2.0L MIL Lamp on VIN: 1P3ES46C9Y
P0171: Fuel System Lean (Bank 1). car fail emission for p0171 no leak car runs great any help wellcome thanks
December 22, 2006
1998 Ford Contour SVT 2.5L MIL Lamp on VIN: 1FALP68GXW
P0171: bank 1 lean. We smoke tested vehicle, no leaks found, except from breather hole at idle air control valve, (not sure if this is normal, have that used smoke machine too often on a ford) Long trim on bank 1 and bank2 max out at 25%, There is no driviablity problem except th...
December 23, 2006
2001 Cadillac Catera 3.0L Misfire, MIL Lamp on VIN: WO6VR54R61
P0171: Fuel Trim System Lean (Bank 1). this vehicle high long term fueltrim. when getting to 23 percent the check engine lite comes on. we cleaned the mass air flow, checked for vac leaks, checked fuel pressure which is 42psi, and replaced a plugged fuel filter. after driving several time the fuel ...
December 27, 2006
2003 Ford E-250 4.2L Poor Fuel Economy, MIL Lamp on VIN: 1FTNS24253
P0171: system too lean b1. ... above the van was good for aprox. 350 miles. Then the MIL came back on with all the same codes excluding the p0300 misfire code. I performed this TSB with care, properly tourging bolts in sequence and cleaning sufaces perfect...
December 29, 2006
1996 Pontiac Grand Am SE 2.4L MIL Lamp on VIN: 1G2NE52T5T
P0171: Fuel System Lean. Hello, First let me apologize for the limited info. I am trying to help a very poor friend get her car fixed and I am in a different city. Ever been there? Also, I am a big rig tech and I only work on cars (mostly Fords) on a limited basis. My question is thi...
December 30, 2006
1996 Pontiac Grand Am SE 2.4L MIL Lamp on VIN: 1G2NE52T5T
P0171: Fuel System Lean. Hello, First let me apologize for the limited info. I am trying to help a very poor friend get her car fixed and I am in a different city. Ever been there? Also, I am a big rig tech and I only work on cars (mostly Fords) on a limited basis. My question is thi...
December 31, 2006
2000 Toyota Tacoma DLX 2.4L MIL Lamp on
P0171: Fuel System Too Lean (Bank 1). ... found dtc p0171 system lean and p0420 cat. problem. we replace oem maf sensor and oem cat.car came back a week later with dtc P0171 so i start checking everything that cause lean problem. vaccum leak, exhaust leak, comprison, fuel pressur, fuel vol. intake...
December 31, 2006