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P0171 Diagnostic Trouble Code Discussion for August 2004

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2000 Nissan Maxima GLE 3.0L Hesitation VIN: JN1CA31D3Y
P0171: Fuel Trim Lean (Bank 1). These 2 codes only seem to appear on an intermittent basis. Cannot find any vacuum leaks, both O2's are cycling and toggling as necessary. Hesitation only seems evident when the car is cold and during warmup and does not occur at all times. I'm a little suspec...
August 03, 2004
1999 Toyota 4Runner SR5 3.4L Poor Fuel Economy, MIL Lamp on VIN: JT3HN86R9X
P0171: Fuel System Too Lean (Bank 1). Hello everyone, I hope someone has seen this and can shed some light on this one for me. Long term fuel trim shoots to +35 under load. Needless to say, the SES lamp is on continous.Have checked all vacuum hoses, connections, tried unplugging VSV for EVAP sys t...
August 08, 2004
1999 Toyota 4Runner SR5 3.4L Poor Fuel Economy, MIL Lamp on VIN: JT3HN86R9X
P0171: Fuel System Too Lean (Bank 1). Hello everyone, I hope someone has seen this and can shed some light on this one for me. Long term fuel trim shoots to +35 under load. Needless to say, the SES lamp is on continous.Have checked all vacuum hoses, connections, tried unplugging VSV for EVAP sys t...
August 09, 2004
2000 Nissan Maxima GLE 3.0L MIL Lamp on VIN: JN1CA31A3Y
P0171: Fuel Trim Lean (Bank 1). Hey everybody, thanks for any help you can offer! Got this maxima in for state inspection / emissions and an oil change. Customer had a complaint of lack of power when pulling into traffic. On the test drive I could only get 1800rpm (cold) up to 2500rpm's on...
August 10, 2004
1997 Nissan Altima GLE 2.4L Misfire, MIL Lamp on VIN: 1N4BU31D7V
P0171: Fuel Trim Lean (Bank 1). ... hoses no diffrance. if you look at o2 its always lean at idle but as you accalrate it starts changing normal .have a miss too may injector.if i change the injector this can take care of p0171 or i have to change MAF too.plea...
August 12, 2004
2003 Pontiac Bonneville SE 3.8L MIL Lamp on VIN: 1G2HX52K13
P0171: Fuel Trim System Lean. ... now! Got this GM with MIL on and code P0171 fuel trim system lean. Checked scan data, fuel trims indicating lean condition. Vehicle runs a little rough when in open loop, and smoothes out with propane. Runs ok in closed loop with ltft at it's limit and sho...
August 12, 2004
2003 Pontiac Bonneville SE 3.8L MIL Lamp on VIN: 1G2HX52K13
P0171: Fuel Trim System Lean. ... now! Got this GM with MIL on and code P0171 fuel trim system lean. Checked scan data, fuel trims indicating lean condition. Vehicle runs a little rough when in open loop, and smoothes out with propane. Runs ok in closed loop with ltft at it's limit and sho...
August 13, 2004
1997 Dodge Ram 1500 Truck 5.9L Excessive Emissions VIN: 3B7HF13ZSV
P0171: Fuel System Lean (Bank 1). ... black smoke after about an hour of towing his fifth wheel camper trailer. MIL comes on with code P0171(system too lean) Also mentioned possible misfire when problem occurs. Please note repair history. I have adjusted distributor sync from 7 degrees back to...
August 17, 2004
1998 Ford F-150 4.2L MIL Lamp on VIN: 2FT2F1720W
P0171: Too lean bank 1. This truck came in with codes P0171 and P0174 Too lean bank #1 & 2. I checked the waveform on the oxygen sensors and found that the front sensors were very noisy. I pulled five gas readings and all the readings were normal and the air to fuel ratio is perf...
August 23, 2004
1997 Ford Aerostar 4.0L MIL Lamp on
P0171: Bank 1 lean. This is my parents car. Last time I was there I cleaned the A/F hotwire and cleared the code, all was fine for a couple months. They went to a local shop who pulled the same code and changed the O2 sensor (only one upsteam of the CAT). CEL came back on the nex...
August 24, 2004
1999 Ford Mustang SVT Cobra 4.6L MIL Lamp on, b1 &b2 lean codes VIN: 1FAFP47V0X
P0171: Bank 1 system too lean memory. ... 1 year with ses light on. I find P0171,0174 lean codes, check mass air flow sensor for oil on it. looks dry but I clean the hot wires with alcohol. Replace the orignal fuel filter (not restricted) for maintenance. found the black duct hose clamp a little l...
August 24, 2004
1996 Ford E-150 Econoline 5.8L MIL Lamp on VIN: 1FMEE11H7T
P0171: Bank 1 sys lean. Hello Everyone. This van has a on going lean code. Owner says mil has been on most of the time. Has tried many times to get this one fixed. I saw a TSB for the 5.8 and 4.9 for the exact problem but does not apply to this cal # 6-64k-ro5. The longterm fuel tri...
August 26, 2004
1999 Ford Mustang SVT Cobra 4.6L MIL Lamp on, b1 &b2 lean codes VIN: 1FAFP47V0X
P0171: Bank 1 system too lean memory. ... 1 year with ses light on. I find P0171,0174 lean codes, check mass air flow sensor for oil on it. looks dry but I clean the hot wires with alcohol. Replace the orignal fuel filter (not restricted) for maintenance. found the black duct hose clamp a little l...
August 26, 2004
1998 Chevrolet K1500 Suburban 5.7L Poor Idle Quality, Misfire, Poor Fuel Economy, MIL Lamp on VIN: 3GKFK16R4W
P0171: Fuel Trim System Lean (Bank 1). vehicle will run fine intermittantly but when it runs bad i have misfires on cylinders 2 4 6 8 the left bank runs fine/ spark plugs are getting fuel fouled. i have found the wiring for the bank 2 sensor 1 pinched between the engine and transmission, i replaced...
August 28, 2004
1999 Toyota Sienna XLE 3.0L MIL Lamp on
P0171: Fuel System Too Lean (Bank 1). Thanks for any help ahead of time, this van came in with a blown head gasket, the tech replaced both, and the van ran great, when the van came back two weeks later it had a po171, and once every to weeks it comes back now. all the vac. numbers have looked good...
August 31, 2004
2000 Nissan Maxima GLE 3.0L Hesitation VIN: JN1CA31D3Y
P0171: Fuel Trim Lean (Bank 1). These 2 codes only seem to appear on an intermittent basis. Cannot find any vacuum leaks, both O2's are cycling and toggling as necessary. Hesitation only seems evident when the car is cold and during warmup and does not occur at all times. I'm a little suspec...
August 03, 2004
1999 Toyota 4Runner SR5 3.4L Poor Fuel Economy, MIL Lamp on VIN: JT3HN86R9X
P0171: Fuel System Too Lean (Bank 1). Hello everyone, I hope someone has seen this and can shed some light on this one for me. Long term fuel trim shoots to +35 under load. Needless to say, the SES lamp is on continous.Have checked all vacuum hoses, connections, tried unplugging VSV for EVAP sys t...
August 08, 2004
1999 Toyota 4Runner SR5 3.4L Poor Fuel Economy, MIL Lamp on VIN: JT3HN86R9X
P0171: Fuel System Too Lean (Bank 1). Hello everyone, I hope someone has seen this and can shed some light on this one for me. Long term fuel trim shoots to +35 under load. Needless to say, the SES lamp is on continous.Have checked all vacuum hoses, connections, tried unplugging VSV for EVAP sys t...
August 09, 2004
2000 Nissan Maxima GLE 3.0L MIL Lamp on VIN: JN1CA31A3Y
P0171: Fuel Trim Lean (Bank 1). Hey everybody, thanks for any help you can offer! Got this maxima in for state inspection / emissions and an oil change. Customer had a complaint of lack of power when pulling into traffic. On the test drive I could only get 1800rpm (cold) up to 2500rpm's on...
August 10, 2004
1997 Nissan Altima GLE 2.4L Misfire, MIL Lamp on VIN: 1N4BU31D7V
P0171: Fuel Trim Lean (Bank 1). ... hoses no diffrance. if you look at o2 its always lean at idle but as you accalrate it starts changing normal .have a miss too may injector.if i change the injector this can take care of p0171 or i have to change MAF too.plea...
August 12, 2004
2003 Pontiac Bonneville SE 3.8L MIL Lamp on VIN: 1G2HX52K13
P0171: Fuel Trim System Lean. ... now! Got this GM with MIL on and code P0171 fuel trim system lean. Checked scan data, fuel trims indicating lean condition. Vehicle runs a little rough when in open loop, and smoothes out with propane. Runs ok in closed loop with ltft at it's limit and sho...
August 12, 2004
2003 Pontiac Bonneville SE 3.8L MIL Lamp on VIN: 1G2HX52K13
P0171: Fuel Trim System Lean. ... now! Got this GM with MIL on and code P0171 fuel trim system lean. Checked scan data, fuel trims indicating lean condition. Vehicle runs a little rough when in open loop, and smoothes out with propane. Runs ok in closed loop with ltft at it's limit and sho...
August 13, 2004
1997 Dodge Ram 1500 Truck 5.9L Excessive Emissions VIN: 3B7HF13ZSV
P0171: Fuel System Lean (Bank 1). ... black smoke after about an hour of towing his fifth wheel camper trailer. MIL comes on with code P0171(system too lean) Also mentioned possible misfire when problem occurs. Please note repair history. I have adjusted distributor sync from 7 degrees back to...
August 17, 2004
1998 Ford F-150 4.2L MIL Lamp on VIN: 2FT2F1720W
P0171: Too lean bank 1. This truck came in with codes P0171 and P0174 Too lean bank #1 & 2. I checked the waveform on the oxygen sensors and found that the front sensors were very noisy. I pulled five gas readings and all the readings were normal and the air to fuel ratio is perf...
August 23, 2004
1997 Ford Aerostar 4.0L MIL Lamp on
P0171: Bank 1 lean. This is my parents car. Last time I was there I cleaned the A/F hotwire and cleared the code, all was fine for a couple months. They went to a local shop who pulled the same code and changed the O2 sensor (only one upsteam of the CAT). CEL came back on the nex...
August 24, 2004
1999 Ford Mustang SVT Cobra 4.6L MIL Lamp on, b1 &b2 lean codes VIN: 1FAFP47V0X
P0171: Bank 1 system too lean memory. ... 1 year with ses light on. I find P0171,0174 lean codes, check mass air flow sensor for oil on it. looks dry but I clean the hot wires with alcohol. Replace the orignal fuel filter (not restricted) for maintenance. found the black duct hose clamp a little l...
August 24, 2004
1996 Ford E-150 Econoline 5.8L MIL Lamp on VIN: 1FMEE11H7T
P0171: Bank 1 sys lean. Hello Everyone. This van has a on going lean code. Owner says mil has been on most of the time. Has tried many times to get this one fixed. I saw a TSB for the 5.8 and 4.9 for the exact problem but does not apply to this cal # 6-64k-ro5. The longterm fuel tri...
August 26, 2004
1999 Ford Mustang SVT Cobra 4.6L MIL Lamp on, b1 &b2 lean codes VIN: 1FAFP47V0X
P0171: Bank 1 system too lean memory. ... 1 year with ses light on. I find P0171,0174 lean codes, check mass air flow sensor for oil on it. looks dry but I clean the hot wires with alcohol. Replace the orignal fuel filter (not restricted) for maintenance. found the black duct hose clamp a little l...
August 26, 2004
1998 Chevrolet K1500 Suburban 5.7L Poor Idle Quality, Misfire, Poor Fuel Economy, MIL Lamp on VIN: 3GKFK16R4W
P0171: Fuel Trim System Lean (Bank 1). vehicle will run fine intermittantly but when it runs bad i have misfires on cylinders 2 4 6 8 the left bank runs fine/ spark plugs are getting fuel fouled. i have found the wiring for the bank 2 sensor 1 pinched between the engine and transmission, i replaced...
August 28, 2004
1999 Toyota Sienna XLE 3.0L MIL Lamp on
P0171: Fuel System Too Lean (Bank 1). Thanks for any help ahead of time, this van came in with a blown head gasket, the tech replaced both, and the van ran great, when the van came back two weeks later it had a po171, and once every to weeks it comes back now. all the vac. numbers have looked good...
August 31, 2004