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P0171 Diagnostic Trouble Code Discussion for September 2009

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2001 Buick Century Custom 3.1L Poor Idle Quality, Stall, MIL Lamp on VIN: 2G4WS52J11
P0171: Fuel System Lean. This one has me baffled! The fuel trims look normal for a few minutes after starting, but then start to climb both at idle and high rpm until they pin. The engine runs fine until the trims go up and then starts running poorly until it stalls. It goes way rich ...
September 02, 2009
2005 GMC Sierra 2500 HD 6.0L Poor Fuel Economy VIN: 1GTHK29UX5
P0171: Fuel Trim System Lean (Bank 1). ... light on. P0171, and P0174, lean bank 1 and 2. LT Fuel trims at +25 only at idle. Off idle they drop to about +14. Short term is consistant around 0 +/- 5. The guy took it to dealership where they told him intake gaskets. There is a updated gasket for thes...
September 02, 2009
2001 Nissan Pathfinder LE 3.5L MIL Lamp on VIN: JN8DR07Y31
P0171: Fuel Trim Lean (Bank 1). ... in with code p0171 lean bank 1.Checked freeze fram data showed fuel trims at LFT B1 134,LFT B2 134,SFT B1 116,SFT B2 114.Smoked intake no leaks found. Fuel pressure is ok.MAF volts 1.31 at idle 171 at 2400 rpm.Don't no why it whould set a code for bank 1 a...
September 03, 2009
2005 Volkswagen Jetta GL 2.0L MIL Lamp on VIN: 3VWSA69M25
P0171: bank 1 system lean. Need some help on this one. This VW will keep setting a PO 171 lean code. Smoked intake system for leaks(none found), inspected all vacuum hoses, checked the oil dipstick tube for cracks- all good. I had replaced the mass airflow sensor for low gp/s readings w...
September 05, 2009
2001 BMW 325xi 2.5L Poor Idle Quality, Misfire, MIL Lamp on VIN: WBAEU33442
P0171: fuel trim limit exceeded rich. ... smoking from the exhaust. No other complaints. By reading the posts here on IATN we were directed to the technical service bulletin regarding the crankcase vent valve. We replaced the valve (purchased from dealer) and the 4 hoses which broke during removal...
September 08, 2009
2004 Ford F-150 Lariat 5.4L MIL Lamp on VIN: 1FTPX145X4
P0171: lean bank 1. Vehicle came in origanally for hard start rough idle, found broken clip at maf sensor, repaired and gone it was. Truck came back for ses light, found poo59 replaced ecm and 02 problem solved(ecm was not applying ground on heater circuit). During drive cycle se...
September 09, 2009
1999 Chevrolet Malibu 3.1L Misfire, MIL Lamp on VIN: 1G1ND52J1X
P0171: Fuel System Lean. ... lower intake manifold gasket replaced due to coolant leak (can you imagine). I gave him estimate and he went elsewhere to have repair done. Now the fun starts. Misfiring since the job was completed. They (the other shop)installed a used fuel rail with used...
September 10, 2009
2002 Subaru Outback 2.5L Poor Idle Quality, Surge, Stall, MIL Lamp on VIN: 4S3BH66572
P0171: Fuel System Too Lean (Bank 1). ... issue. I went after the p0065 code first. Usually the air assist solenoid will give me a IAC code when it fails. I verified solenoid clicks when ground is supplied and engine runs differently. I have a small vaccum when checked on the throtle body side of ...
September 10, 2009
2001 Honda Civic EX 1.7L Poor Idle Quality, Stall, MIL Lamp on VIN: 1HGEM21241
P0171: Fuel System Too Lean. po171 lean bank 1 stored in system. Customer complains of a poor idle at stop lights and then it will stall. This only occurs when the fuel level is at 1/4 tank or lower so he says. He also complains of excess crank time when it is hot. So far both times I hav...
September 11, 2009
1996 Toyota Land Cruiser 4.5L MIL Lamp on VIN: JT3HJ85J6T
P0171: Fuel System Too Lean (Bank 1). hello i don't know if anyone has had this problem but this landcruier has a intermittent bank one lean. every time it's at our shop all my fuel trims are ok. i road test to see if i can get my code and all fuel trims are good no vacuum leak, smoke test intake....
September 11, 2009
2005 Volkswagen Jetta GL 2.0L MIL Lamp on VIN: 3VWSA69M25
P0171: bank 1 system lean. Need some help on this one. This VW will keep setting a PO 171 lean code. Smoked intake system for leaks(none found), inspected all vacuum hoses, checked the oil dipstick tube for cracks- all good. I had replaced the mass airflow sensor for low gp/s readings w...
September 11, 2009
2005 Audi A4 Quattro 1.8L Poor Idle Quality, Misfire, MIL Lamp on VIN: WAULC68E15
P0171: system too lean bank 1. runs very rough and mil flashes at idle. runs fine with foot on brake and in gear if rpm is above 1100 rpm. MAF reads higher than alldata says it should at idle. checked power, ground and 5 volt ref. all ok. Replaced MAF with new bosch from aftermarket suppli...
September 15, 2009
2006 Dodge Charger SXT 3.5L Stall, MIL Lamp on VIN: 2B3KA46G56
P0171: Fuel System Lean (Bank 1). ... time officer states car stalls at idle and at highway speeds it allways restart vehicle has not duplicated the symtom while in the shop but has come in twice with the same codes pending codes are po42o and p0430 freeze frame po174 engine run 48min 45 sec t...
September 15, 2009
2000 Nissan Maxima GLE 3.0L Poor Idle Quality, Hesitation, Cuts out, Stall, MIL Lamp on VIN: JN1CA31A2Y
P0171: Fuel Trim Lean (Bank 1). hello in first, am french and my english is very poor... i have a trouble whit a maxima 2000 ,the idle is very bad (up end down) at cold,the o2 sensor is lean at 0.02v ,no activity.when i put the throtle wot,max rev limit is 3000RPM always in lean condition ....
September 16, 2009
2004 Chevrolet Trailblazer LS 4.2L MIL Lamp on VIN: IGNDS13S34
P0171: Fuel System Lean (Bank 1). ... I never even heard before!!! The fuel pressure is steady 57 @ idle, and 50@ cruise!!! The fuel trim goes very hi on cruise (20 st and 27 lt), and sets codes for rich and lean system. Also sets code p1133 O2 not switching...
September 18, 2009
2002 Pontiac Firebird Trans Am 5.7L MIL Lamp on VIN: 2G2FV22G52
P0171: Fuel Trim System Lean (Bank 1). ... rid of p0171,p0174.This car is my sons new car he just had to have,with out being checked by a shop.I went to virgina and towed it back when he could not drive it no more due to fuel leak,oil leak.I installed a new delco fuel pump in tank after removeing t...
September 19, 2009
2004 Chevrolet Trailblazer LS 4.2L MIL Lamp on VIN: IGNDS13S34
P0171: Fuel System Lean (Bank 1). ... I never even heard before!!! The fuel pressure is steady 57 @ idle, and 50@ cruise!!! The fuel trim goes very hi on cruise (20 st and 27 lt), and sets codes for rich and lean system. Also sets code p1133 O2 not switching...
September 21, 2009
1996 Oldsmobile Cutlass Supreme SL 3.1L MIL Lamp on VIN: 1G3WH52M9T
P0171: Fuel System Lean (Bank 1). dtc p0336 comes on after [...] of running everytime. other dtc's come on not all the time but has to run for a while. have replaced pcm, cam sensor, crank sensor and tone wheel is good. replaced mass air flow sensor, and ignition control module also.
September 21, 2009
1995 Buick Park Avenue Ultra 3.8L MIL Lamp on, p0171
P0171: system lean. replaced o2 this solved p0132, but p0171 popped back up?? o2 switches slow at idle(stays lean) and switches o.k. under load.
September 22, 2009
2006 Audi A4 2.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: WAUF78E26A
P0171: lean. ... with the P0171 and P0507 and accompanying MIL, but running fine. I scanned and retrieved the codes, monitored and verified the very lean condition by fuel trims. I sprayed for leaks, checked and rechecked and the only leak...
September 23, 2009
2004 Lexus RX330 3.3L Poor Idle Quality, Hesitation, Cuts out, Stall, MIL Lamp on VIN: 272GA31U54
P0171: Fuel System Too Lean (Bank 1). ... atlanta day after very significant flooding. Customer states that no flood waters were encountered with vehicle. As you can see with the tests already performed on the vehicle, all tests concerning driveability are within normal values. after revving mo...
September 23, 2009
2007 Pontiac Solstice 2.4L Misfire, MIL Lamp on VIN: 1G2MB35B47
P0171: Fuel System Lean. what happens is that for the first 2-3mins of running oxygen sensor upstream is switching properly and then it will go to 10mv and just sit there no switch no nothing, downstream oxygen sensor reads almost 1000mv while problem is occuring. now being a flood vi...
September 24, 2009
2005 BMW X3 3.0i 3.0L MIL Lamp on VIN: WBXPA93485
P0171: lean bank 1. This bimmer came in with a po171 and I cleared it and it took 400 miles to return, this time it had po171,po174 so I replaced the parts listed above. The long term trim is 7.8% on both banks so I know this light is coming back, short term seems to be mainly le...
September 26, 2009
2006 Ford Five Hundred Limited 3.0L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1FAFP25176
P0171: system to lean bank 1. ... The next morning it started and seen that the MIL was on. Never seen so many codes. P0106,P0171,P0175,P0340,P0353,P0355,P0356,P1336,P1297 AND P2198. I did run a VIN check and it came up a...
September 29, 2009
2005 Volkswagen Touareg 4.2L Stall VIN: WVGCM77L65
P0171: lean. vehicle starts and runs then stalls after 1-2 min. due to loss of fuel pressure. transfer pump supplies 60 psi at 8.5 amps then the pressure drops and the amps move to zero. I think that the fuel pump should take over fuel supply at this time because it has po...
September 29, 2009
2005 Mercury Grand Marquis GS 4.6L MIL Lamp on VIN: 2MEFM74W75
P0171: bank 1 lean. car runs great and the only complaint is the check engine light is on. only codes are po171 & po174 both lean codes. i installed a new fuel filter ( never been changed )scanned the o2 while driveing and they both seem to change rich to lean ( slow but i've...
September 30, 2009
2001 Buick Century Custom 3.1L Poor Idle Quality, Stall, MIL Lamp on VIN: 2G4WS52J11
P0171: Fuel System Lean. This one has me baffled! The fuel trims look normal for a few minutes after starting, but then start to climb both at idle and high rpm until they pin. The engine runs fine until the trims go up and then starts running poorly until it stalls. It goes way rich ...
September 02, 2009
2005 GMC Sierra 2500 HD 6.0L Poor Fuel Economy VIN: 1GTHK29UX5
P0171: Fuel Trim System Lean (Bank 1). ... light on. P0171, and P0174, lean bank 1 and 2. LT Fuel trims at +25 only at idle. Off idle they drop to about +14. Short term is consistant around 0 +/- 5. The guy took it to dealership where they told him intake gaskets. There is a updated gasket for thes...
September 02, 2009
2001 Nissan Pathfinder LE 3.5L MIL Lamp on VIN: JN8DR07Y31
P0171: Fuel Trim Lean (Bank 1). ... in with code p0171 lean bank 1.Checked freeze fram data showed fuel trims at LFT B1 134,LFT B2 134,SFT B1 116,SFT B2 114.Smoked intake no leaks found. Fuel pressure is ok.MAF volts 1.31 at idle 171 at 2400 rpm.Don't no why it whould set a code for bank 1 a...
September 03, 2009
2005 Volkswagen Jetta GL 2.0L MIL Lamp on VIN: 3VWSA69M25
P0171: bank 1 system lean. Need some help on this one. This VW will keep setting a PO 171 lean code. Smoked intake system for leaks(none found), inspected all vacuum hoses, checked the oil dipstick tube for cracks- all good. I had replaced the mass airflow sensor for low gp/s readings w...
September 05, 2009
2001 BMW 325xi 2.5L Poor Idle Quality, Misfire, MIL Lamp on VIN: WBAEU33442
P0171: fuel trim limit exceeded rich. ... smoking from the exhaust. No other complaints. By reading the posts here on IATN we were directed to the technical service bulletin regarding the crankcase vent valve. We replaced the valve (purchased from dealer) and the 4 hoses which broke during removal...
September 08, 2009
2004 Ford F-150 Lariat 5.4L MIL Lamp on VIN: 1FTPX145X4
P0171: lean bank 1. Vehicle came in origanally for hard start rough idle, found broken clip at maf sensor, repaired and gone it was. Truck came back for ses light, found poo59 replaced ecm and 02 problem solved(ecm was not applying ground on heater circuit). During drive cycle se...
September 09, 2009
1999 Chevrolet Malibu 3.1L Misfire, MIL Lamp on VIN: 1G1ND52J1X
P0171: Fuel System Lean. ... lower intake manifold gasket replaced due to coolant leak (can you imagine). I gave him estimate and he went elsewhere to have repair done. Now the fun starts. Misfiring since the job was completed. They (the other shop)installed a used fuel rail with used...
September 10, 2009
2002 Subaru Outback 2.5L Poor Idle Quality, Surge, Stall, MIL Lamp on VIN: 4S3BH66572
P0171: Fuel System Too Lean (Bank 1). ... issue. I went after the p0065 code first. Usually the air assist solenoid will give me a IAC code when it fails. I verified solenoid clicks when ground is supplied and engine runs differently. I have a small vaccum when checked on the throtle body side of ...
September 10, 2009
2001 Honda Civic EX 1.7L Poor Idle Quality, Stall, MIL Lamp on VIN: 1HGEM21241
P0171: Fuel System Too Lean. po171 lean bank 1 stored in system. Customer complains of a poor idle at stop lights and then it will stall. This only occurs when the fuel level is at 1/4 tank or lower so he says. He also complains of excess crank time when it is hot. So far both times I hav...
September 11, 2009
1996 Toyota Land Cruiser 4.5L MIL Lamp on VIN: JT3HJ85J6T
P0171: Fuel System Too Lean (Bank 1). hello i don't know if anyone has had this problem but this landcruier has a intermittent bank one lean. every time it's at our shop all my fuel trims are ok. i road test to see if i can get my code and all fuel trims are good no vacuum leak, smoke test intake....
September 11, 2009
2005 Volkswagen Jetta GL 2.0L MIL Lamp on VIN: 3VWSA69M25
P0171: bank 1 system lean. Need some help on this one. This VW will keep setting a PO 171 lean code. Smoked intake system for leaks(none found), inspected all vacuum hoses, checked the oil dipstick tube for cracks- all good. I had replaced the mass airflow sensor for low gp/s readings w...
September 11, 2009
2005 Audi A4 Quattro 1.8L Poor Idle Quality, Misfire, MIL Lamp on VIN: WAULC68E15
P0171: system too lean bank 1. runs very rough and mil flashes at idle. runs fine with foot on brake and in gear if rpm is above 1100 rpm. MAF reads higher than alldata says it should at idle. checked power, ground and 5 volt ref. all ok. Replaced MAF with new bosch from aftermarket suppli...
September 15, 2009
2006 Dodge Charger SXT 3.5L Stall, MIL Lamp on VIN: 2B3KA46G56
P0171: Fuel System Lean (Bank 1). ... time officer states car stalls at idle and at highway speeds it allways restart vehicle has not duplicated the symtom while in the shop but has come in twice with the same codes pending codes are po42o and p0430 freeze frame po174 engine run 48min 45 sec t...
September 15, 2009
2000 Nissan Maxima GLE 3.0L Poor Idle Quality, Hesitation, Cuts out, Stall, MIL Lamp on VIN: JN1CA31A2Y
P0171: Fuel Trim Lean (Bank 1). hello in first, am french and my english is very poor... i have a trouble whit a maxima 2000 ,the idle is very bad (up end down) at cold,the o2 sensor is lean at 0.02v ,no activity.when i put the throtle wot,max rev limit is 3000RPM always in lean condition ....
September 16, 2009
2004 Chevrolet Trailblazer LS 4.2L MIL Lamp on VIN: IGNDS13S34
P0171: Fuel System Lean (Bank 1). ... I never even heard before!!! The fuel pressure is steady 57 @ idle, and 50@ cruise!!! The fuel trim goes very hi on cruise (20 st and 27 lt), and sets codes for rich and lean system. Also sets code p1133 O2 not switching...
September 18, 2009
2002 Pontiac Firebird Trans Am 5.7L MIL Lamp on VIN: 2G2FV22G52
P0171: Fuel Trim System Lean (Bank 1). ... rid of p0171,p0174.This car is my sons new car he just had to have,with out being checked by a shop.I went to virgina and towed it back when he could not drive it no more due to fuel leak,oil leak.I installed a new delco fuel pump in tank after removeing t...
September 19, 2009
2004 Chevrolet Trailblazer LS 4.2L MIL Lamp on VIN: IGNDS13S34
P0171: Fuel System Lean (Bank 1). ... I never even heard before!!! The fuel pressure is steady 57 @ idle, and 50@ cruise!!! The fuel trim goes very hi on cruise (20 st and 27 lt), and sets codes for rich and lean system. Also sets code p1133 O2 not switching...
September 21, 2009
1996 Oldsmobile Cutlass Supreme SL 3.1L MIL Lamp on VIN: 1G3WH52M9T
P0171: Fuel System Lean (Bank 1). dtc p0336 comes on after [...] of running everytime. other dtc's come on not all the time but has to run for a while. have replaced pcm, cam sensor, crank sensor and tone wheel is good. replaced mass air flow sensor, and ignition control module also.
September 21, 2009
1995 Buick Park Avenue Ultra 3.8L MIL Lamp on, p0171
P0171: system lean. replaced o2 this solved p0132, but p0171 popped back up?? o2 switches slow at idle(stays lean) and switches o.k. under load.
September 22, 2009
2006 Audi A4 2.0L Poor Idle Quality, Misfire, MIL Lamp on VIN: WAUF78E26A
P0171: lean. ... with the P0171 and P0507 and accompanying MIL, but running fine. I scanned and retrieved the codes, monitored and verified the very lean condition by fuel trims. I sprayed for leaks, checked and rechecked and the only leak...
September 23, 2009
2004 Lexus RX330 3.3L Poor Idle Quality, Hesitation, Cuts out, Stall, MIL Lamp on VIN: 272GA31U54
P0171: Fuel System Too Lean (Bank 1). ... atlanta day after very significant flooding. Customer states that no flood waters were encountered with vehicle. As you can see with the tests already performed on the vehicle, all tests concerning driveability are within normal values. after revving mo...
September 23, 2009
2007 Pontiac Solstice 2.4L Misfire, MIL Lamp on VIN: 1G2MB35B47
P0171: Fuel System Lean. what happens is that for the first 2-3mins of running oxygen sensor upstream is switching properly and then it will go to 10mv and just sit there no switch no nothing, downstream oxygen sensor reads almost 1000mv while problem is occuring. now being a flood vi...
September 24, 2009
2005 BMW X3 3.0i 3.0L MIL Lamp on VIN: WBXPA93485
P0171: lean bank 1. This bimmer came in with a po171 and I cleared it and it took 400 miles to return, this time it had po171,po174 so I replaced the parts listed above. The long term trim is 7.8% on both banks so I know this light is coming back, short term seems to be mainly le...
September 26, 2009
2006 Ford Five Hundred Limited 3.0L No Start, Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1FAFP25176
P0171: system to lean bank 1. ... The next morning it started and seen that the MIL was on. Never seen so many codes. P0106,P0171,P0175,P0340,P0353,P0355,P0356,P1336,P1297 AND P2198. I did run a VIN check and it came up a...
September 29, 2009
2005 Volkswagen Touareg 4.2L Stall VIN: WVGCM77L65
P0171: lean. vehicle starts and runs then stalls after 1-2 min. due to loss of fuel pressure. transfer pump supplies 60 psi at 8.5 amps then the pressure drops and the amps move to zero. I think that the fuel pump should take over fuel supply at this time because it has po...
September 29, 2009
2005 Mercury Grand Marquis GS 4.6L MIL Lamp on VIN: 2MEFM74W75
P0171: bank 1 lean. car runs great and the only complaint is the check engine light is on. only codes are po171 & po174 both lean codes. i installed a new fuel filter ( never been changed )scanned the o2 while driveing and they both seem to change rich to lean ( slow but i've...
September 30, 2009