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P0171 Diagnostic Trouble Code Discussion for January 2005

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
1999 Ford Windstar SE 3.0L MIL Lamp on VIN: 2FMZA5246X
P0171: system lean. Sorry but boss not around. I m on his accountto get some help. But vehicle came in for check engine light. Pulled code and found code common code for this vehicle PO171. No visible leak in intake and exhaust during time of test. Baromenter checked ok at 150 hz...
January 03, 2005
1999 Ford Windstar SE 3.0L MIL Lamp on VIN: 2FMZA5246X
P0171: system lean. Sorry but boss not around. I m on his accountto get some help. But vehicle came in for check engine light. Pulled code and found code common code for this vehicle PO171. No visible leak in intake and exhaust during time of test. Baromenter checked ok at 150 hz...
January 04, 2005
1996 Toyota Tacoma DLX 3.4L Poor Idle Quality, MIL Lamp on VIN: 4TAWN72N7T
P0171: Fuel System Too Lean (Bank 1). ... complaint and a mil. P0171 was pulled from computer. Inspected maf sensor and discovered rodent damage to air filter. Maf sensor was covered with dirt,pieces of filter and rodent hair. That hair is wrapped around the elements and the elements are way down ...
January 05, 2005
2000 Nissan Maxima GLE 3.0L MIL Lamp on, lacks power uphill VIN: JN1CA31D2Y
P0171: Fuel Trim Lean (Bank 1). Good morning, vehicle lacks power uphills and sometimes pings. LT fuel trim is 34% on both banks. ST fuel trim is 16%both banks. Emmissions are good. O2 sensors are working. fuel filter is in tank. there is no servive port to check fuel pressure. It looks like...
January 07, 2005
2001 Mazda MPV DX 2.5L Excessive Emissions VIN: JM3LW28Y11
P0171: Adaptive Fuel Trim Too Lean (Bank 1). My question is, is there a common problem that will cause both #1 O2 sensors to read bad at the same time? I have seen this on Fords and have fixed vaccum lines to repair this problem without replacing O2 sensors. This vehicle has never had a tune-up. That is ...
January 12, 2005
1999 Mazda Protege DX 1.6L MIL Lamp on VIN: JM1BJ2225X
P0171: Adaptive Fuel Trim Too Lean (Bank 1). replaced bank1 o2 senser light came back on within a day i need to know if any tsbs are on this problem also were to start on trouble shooting this problem note engine temp was 196 f on freeze data
January 13, 2005
2001 Honda Accord EX 3.0L MIL Lamp on VIN: 1HGCG16521
P0171: Fuel System Too Lean (Bank 1). Car came in with mil on,code 171 lean.Car runs good long term trim was at 20,short term at 30 and above at idle.at cruise both trim values drop close to zero.smoke test intake for leaks and none were found.blocked off egr valve just to make sure there was no l...
January 20, 2005
2001 Volvo V70 2.4L MIL Lamp on VIN: YV1SW61N01
P0171: system lean. ... and now the MIL is on. W/P0171 (system too lean). We have checked it out for vacuum leaks with smoke and propan and none are apparent. We have cleaned the Air Mass Meter however the light returns fairly quickly. My question is, I thought these were two or...
January 20, 2005
1996 Chevrolet Monte Carlo LS 3.1L Poor Idle Quality, MIL Lamp on VIN: 2G1WW12M9T
P0171: Fuel System Lean (Bank 1). ... it failed the emmision test and that the mil was on. Scanned for codes, none found. While observing scanner data I noticed that the idle did not want drop below 1300rpm and if you tried to control the IAC the rpm would only go up. I checked the PCM power a...
January 21, 2005
2001 Ford F-150 XL 4.2L MIL Lamp on, eng. noises times VIN: 1FTZX172X1
P0171: lean bank 1. ... will set P0171 and P0174 codes for lean on both banks. Freeze frames show the it is set low speeds and LTFT are 7-9 on both banks. I have check fuel pressure and check for vac leaks. I had a lazy o2 sensor on bank 1 couple months ago. So replaced both frt....
January 21, 2005
1997 Ford E-350 Econoline 5.4L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1FDKE37L3V
P0171: System to lean bank 1. Hello all. This headache was towed in unable to start. A quick check showed a lack of fuel problem so the first check was the fuel filter. It was clogged solid - could not blow through it at all! Replaced fuel filter and was able to get vehicle started. vehicl...
January 25, 2005
2000 Ford Explorer Limited 4.0L MIL Lamp on VIN: 1FMZU75EXY
P0171: lean bank 1 sensor 1. THIS vehicle continues to come back with lean codes on either one bank or both depending on how long you drive it. It seems to trake about two weeks of normal driving to trip the MIL. The freeze frame data at last chech showed 39MPH, 40% load, STFT bank 0ne -3...
January 25, 2005
1996 Chevrolet Monte Carlo LS 3.1L Poor Idle Quality, MIL Lamp on VIN: 2G1WW12M9T
P0171: Fuel System Lean (Bank 1). ... it failed the emmision test and that the mil was on. Scanned for codes, none found. While observing scanner data I noticed that the idle did not want drop below 1300rpm and if you tried to control the IAC the rpm would only go up. I checked the PCM power a...
January 26, 2005
1997 Ford E-350 Econoline 5.4L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1FDKE37L3V
P0171: System to lean bank 1. Hello all. This headache was towed in unable to start. A quick check showed a lack of fuel problem so the first check was the fuel filter. It was clogged solid - could not blow through it at all! Replaced fuel filter and was able to get vehicle started. vehicl...
January 26, 2005
2000 Toyota Tundra 3.4L Hesitation, Poor Fuel Economy, MIL Lamp on VIN: 5TBJN3213Y
P0171: Fuel System Too Lean (Bank 1). Hello all, This one is back. Last week I replaced plugs and filters and cleaned maf sensor,checked for air leaks, etc.. It had both rich and lean codes so I was thinking maf sensor. I turned off the lite and gave it back to the customer with a warning that we ...
January 27, 2005
1997 Ford Explorer Sport 4.0L MIL Lamp on VIN: 1FMCU22X9V
P0171: b1s1 lean code. truck came back in today with the same lean codes. when i scanned the computer i found all the 02 readings were at 0.000 volts .no change with propane added. this o volts is on all three 02 sensors. tried a differant scanner and got the same readings. zero he...
January 28, 2005
1997 Ford F-150 4.6L MIL Lamp on
P0171: System lean Bank 1. ... it's maxim fuel trim +35% and scaner some times say's error on fuel trim. Is setting P0171 & P0174 sys. lean codes. I have cleand and inspected MAF sensor looks good an reads good. o2's are switching/crosing center ok little slow but they are switching...
January 28, 2005
2000 Ford Mustang 3.8L MIL Lamp on VIN: 1FAFP4447Y
P0171: long term fuel trim is over 23. mil ligth comes on after driven a while, again tdc's are po171,po174, did a vaccum leak test using smoke machine, no leak found. fuel pressure is 35 psi and 45psi no vacc map reading is at [...]/sec and at 2500 rpm is 12.5gsr/sec thi vehicle does not have a pl...
January 28, 2005
1997 Ford F-150 4.6L MIL Lamp on
P0171: System lean Bank 1. ... it's maxim fuel trim +35% and scaner some times say's error on fuel trim. Is setting P0171 & P0174 sys. lean codes. I have cleand and inspected MAF sensor looks good an reads good. o2's are switching/crosing center ok little slow but they are switching...
January 30, 2005
1999 Ford Windstar SE 3.0L MIL Lamp on VIN: 2FMZA5246X
P0171: system lean. Sorry but boss not around. I m on his accountto get some help. But vehicle came in for check engine light. Pulled code and found code common code for this vehicle PO171. No visible leak in intake and exhaust during time of test. Baromenter checked ok at 150 hz...
January 03, 2005
1999 Ford Windstar SE 3.0L MIL Lamp on VIN: 2FMZA5246X
P0171: system lean. Sorry but boss not around. I m on his accountto get some help. But vehicle came in for check engine light. Pulled code and found code common code for this vehicle PO171. No visible leak in intake and exhaust during time of test. Baromenter checked ok at 150 hz...
January 04, 2005
1996 Toyota Tacoma DLX 3.4L Poor Idle Quality, MIL Lamp on VIN: 4TAWN72N7T
P0171: Fuel System Too Lean (Bank 1). ... complaint and a mil. P0171 was pulled from computer. Inspected maf sensor and discovered rodent damage to air filter. Maf sensor was covered with dirt,pieces of filter and rodent hair. That hair is wrapped around the elements and the elements are way down ...
January 05, 2005
2000 Nissan Maxima GLE 3.0L MIL Lamp on, lacks power uphill VIN: JN1CA31D2Y
P0171: Fuel Trim Lean (Bank 1). Good morning, vehicle lacks power uphills and sometimes pings. LT fuel trim is 34% on both banks. ST fuel trim is 16%both banks. Emmissions are good. O2 sensors are working. fuel filter is in tank. there is no servive port to check fuel pressure. It looks like...
January 07, 2005
2001 Mazda MPV DX 2.5L Excessive Emissions VIN: JM3LW28Y11
P0171: Adaptive Fuel Trim Too Lean (Bank 1). My question is, is there a common problem that will cause both #1 O2 sensors to read bad at the same time? I have seen this on Fords and have fixed vaccum lines to repair this problem without replacing O2 sensors. This vehicle has never had a tune-up. That is ...
January 12, 2005
1999 Mazda Protege DX 1.6L MIL Lamp on VIN: JM1BJ2225X
P0171: Adaptive Fuel Trim Too Lean (Bank 1). replaced bank1 o2 senser light came back on within a day i need to know if any tsbs are on this problem also were to start on trouble shooting this problem note engine temp was 196 f on freeze data
January 13, 2005
2001 Honda Accord EX 3.0L MIL Lamp on VIN: 1HGCG16521
P0171: Fuel System Too Lean (Bank 1). Car came in with mil on,code 171 lean.Car runs good long term trim was at 20,short term at 30 and above at idle.at cruise both trim values drop close to zero.smoke test intake for leaks and none were found.blocked off egr valve just to make sure there was no l...
January 20, 2005
2001 Volvo V70 2.4L MIL Lamp on VIN: YV1SW61N01
P0171: system lean. ... and now the MIL is on. W/P0171 (system too lean). We have checked it out for vacuum leaks with smoke and propan and none are apparent. We have cleaned the Air Mass Meter however the light returns fairly quickly. My question is, I thought these were two or...
January 20, 2005
1996 Chevrolet Monte Carlo LS 3.1L Poor Idle Quality, MIL Lamp on VIN: 2G1WW12M9T
P0171: Fuel System Lean (Bank 1). ... it failed the emmision test and that the mil was on. Scanned for codes, none found. While observing scanner data I noticed that the idle did not want drop below 1300rpm and if you tried to control the IAC the rpm would only go up. I checked the PCM power a...
January 21, 2005
2001 Ford F-150 XL 4.2L MIL Lamp on, eng. noises times VIN: 1FTZX172X1
P0171: lean bank 1. ... will set P0171 and P0174 codes for lean on both banks. Freeze frames show the it is set low speeds and LTFT are 7-9 on both banks. I have check fuel pressure and check for vac leaks. I had a lazy o2 sensor on bank 1 couple months ago. So replaced both frt....
January 21, 2005
1997 Ford E-350 Econoline 5.4L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1FDKE37L3V
P0171: System to lean bank 1. Hello all. This headache was towed in unable to start. A quick check showed a lack of fuel problem so the first check was the fuel filter. It was clogged solid - could not blow through it at all! Replaced fuel filter and was able to get vehicle started. vehicl...
January 25, 2005
2000 Ford Explorer Limited 4.0L MIL Lamp on VIN: 1FMZU75EXY
P0171: lean bank 1 sensor 1. THIS vehicle continues to come back with lean codes on either one bank or both depending on how long you drive it. It seems to trake about two weeks of normal driving to trip the MIL. The freeze frame data at last chech showed 39MPH, 40% load, STFT bank 0ne -3...
January 25, 2005
1996 Chevrolet Monte Carlo LS 3.1L Poor Idle Quality, MIL Lamp on VIN: 2G1WW12M9T
P0171: Fuel System Lean (Bank 1). ... it failed the emmision test and that the mil was on. Scanned for codes, none found. While observing scanner data I noticed that the idle did not want drop below 1300rpm and if you tried to control the IAC the rpm would only go up. I checked the PCM power a...
January 26, 2005
1997 Ford E-350 Econoline 5.4L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1FDKE37L3V
P0171: System to lean bank 1. Hello all. This headache was towed in unable to start. A quick check showed a lack of fuel problem so the first check was the fuel filter. It was clogged solid - could not blow through it at all! Replaced fuel filter and was able to get vehicle started. vehicl...
January 26, 2005
2000 Toyota Tundra 3.4L Hesitation, Poor Fuel Economy, MIL Lamp on VIN: 5TBJN3213Y
P0171: Fuel System Too Lean (Bank 1). Hello all, This one is back. Last week I replaced plugs and filters and cleaned maf sensor,checked for air leaks, etc.. It had both rich and lean codes so I was thinking maf sensor. I turned off the lite and gave it back to the customer with a warning that we ...
January 27, 2005
1997 Ford Explorer Sport 4.0L MIL Lamp on VIN: 1FMCU22X9V
P0171: b1s1 lean code. truck came back in today with the same lean codes. when i scanned the computer i found all the 02 readings were at 0.000 volts .no change with propane added. this o volts is on all three 02 sensors. tried a differant scanner and got the same readings. zero he...
January 28, 2005
1997 Ford F-150 4.6L MIL Lamp on
P0171: System lean Bank 1. ... it's maxim fuel trim +35% and scaner some times say's error on fuel trim. Is setting P0171 & P0174 sys. lean codes. I have cleand and inspected MAF sensor looks good an reads good. o2's are switching/crosing center ok little slow but they are switching...
January 28, 2005
2000 Ford Mustang 3.8L MIL Lamp on VIN: 1FAFP4447Y
P0171: long term fuel trim is over 23. mil ligth comes on after driven a while, again tdc's are po171,po174, did a vaccum leak test using smoke machine, no leak found. fuel pressure is 35 psi and 45psi no vacc map reading is at [...]/sec and at 2500 rpm is 12.5gsr/sec thi vehicle does not have a pl...
January 28, 2005
1997 Ford F-150 4.6L MIL Lamp on
P0171: System lean Bank 1. ... it's maxim fuel trim +35% and scaner some times say's error on fuel trim. Is setting P0171 & P0174 sys. lean codes. I have cleand and inspected MAF sensor looks good an reads good. o2's are switching/crosing center ok little slow but they are switching...
January 30, 2005