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P0171 Diagnostic Trouble Code Discussion for April 2007

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2000 Toyota Solara SE 3.0L MIL Lamp on VIN: 2T1CF22P7Y
P0171: System lean Bank 1. ... failing at a smog station. After testing we changed the B1S1 O2 sensor and MAF sensor. We are still getting a code P0171 after resetting the monitors. Sometimes it will set all the monitors without setting the code. Then, next startup the light will come o...
April 03, 2007
1996 Chevrolet Cavalier Z24 2.4L Misfire, MIL Lamp on VIN: 1G1JF12T1T
P0171: Fuel System Lean (Bank 1). ... car will run great sometimes for hours or days then out of the blue starts misfiring backfiring pooring black smoke then next time you start engine it may run fine or not. ckp \cmp signal ok codes p0171 lean bank 1\p0300 m...
April 04, 2007
2001 Ford Focus ZX3 2.0L MIL Lamp on VIN: 3FAFP31391
P0171: lean bank 1. ... it has been in my shop on and off for the past year with the same code P0171. My long term fuel trim is around 25% and the short is about .3 +/-. It has has a new o2 sensor, mass air flow, fuel pump (at the dealer) I replaced egr last time for a seperate i...
April 04, 2007
2001 Ford F-150 XL 4.2L MIL Lamp on VIN: 1FTZF17221
P0171: bank 1 lean condition. ... engine light on. The code was p0171 (lean condition bank 1). Typically on these Fords we followed the service bulletin for the upper intake manifold gaskets internally leaking. We changed all seals, gaskets and pcv valve and cleaned everything up. The cust...
April 05, 2007
2002 Ford Windstar LX 3.8L MIL Lamp on VIN: 2FMZA51472
P0171: lean condition bank 1. ... plain stumping me. It came from the used car lot we sublet for. originally we found 10 dtcs stored and found 4 issues. we replaced the lower intake manifold due to a vacuum leak around imrc shaft, we found it with smoke. bank 1 o2 for no operation. after t...
April 05, 2007
2001 Isuzu Rodeo LS 3.2L Hesitation, Stall, MIL Lamp on VIN: 4S2DM58W61
P0171: Fuel System Too Lean (Bank 1). at 1,500 or 2,500 ltft = + 22 all o2's less than 100 mv fuel pressure = 47 passes noid light test passes injector pressure drop test maf looks good on the lab scope i need some ideas on what to test next
April 05, 2007
2000 Nissan Sentra SE 2.0L Hesitation VIN: 3N1BB51D8Y
P0171: Fuel Trim Lean. We have this Sentra with a P0171 Code. Looking at other Nissans on IATN looks like 99% of the cause is a bad MAF sensor. We tested it according to All Data and at 2500 rpm we got about 1.35 volts and at 4000 rpm 1.89 volts. Never got above 2.5 volts when revvi...
April 06, 2007
1995 Chevrolet S10 LS 4.3L Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1GCCS19Z3S
P0171: Exaust Lean. ... The customer changed IAC, TPS, O2, no change. I pluged in my scan tool (Mastertech) and noticed iregular data stream, like system voltage droping to 2.4v or a RPM reeding of 99999, and code 55 amoung others. I checked all powers and grounds, and all the so...
April 12, 2007
1999 Ford Explorer XL 4.0L MIL Lamp on VIN: 1FMZ34X6XV
P0171: ltft. The car came mising codes in ECM P0171 P0174 LTFT lean [...]. Tune up and wire intake manfold uper and lower replace mass. car came back p0171 p0174 ltft# 5 to 10%.
April 16, 2007
2000 Nissan Maxima GLE 3.0L MIL Lamp on, Hard to start VIN: JN1CA31A8Y
P0171: Fuel Trim Lean (Bank 1). I know some Nissans like to have injector failures and I'm not sure if this car has the same common issue. I do not get rough running myself here but the customer is complaining about rough start up. I recently replaced the throttle body o-ring which was allow...
April 17, 2007
2001 BMW 525i 2.5L MIL Lamp on VIN: WBADT43481
P0171: Bank 1 lean. Alright, this one is bugging the hell out of me. Got this 01 BMW with lean codes. Runs fine with plenty of zip in it. Fuel trims are as follows: idle-STFT 8% LTFT 10% (both banks) cruise-switching bewteen -3% to 4% LTFT 8%. 02's switching nice. Fuel pressure g...
April 18, 2007
2001 Volkswagen Passat GLS 1.8L MIL Lamp on VIN: WVWPD63B61
P0171: system lean bank 1. ... light on with a code p0171 system lean bank #1. Car was in six months ago for the same code we installed a MAF sensor all was well until now. Car runs good, checked car for vacuume leaks none were found. Cleand throtle body light came back on. I saw some o...
April 19, 2007
1999 Chevrolet Camaro 3.8L Misfire, MIL Lamp on VIN: 2G1FP22K7X
P0171: Fuel Trim System Lean (Bank 1). THIS FOR A CO-WORKER,.. original complaint was no heat,..intake gasket was leaking,.NO driveability problems at that time. Replaced gaskets,..delivered car 3 days later check engine light on,..idles good when cold,..as engine warms up noticeable "shake"...
April 24, 2007
2001 Volkswagen Jetta GLS 2.0L MIL Lamp on VIN: 3VWSB69M01
P0171: System lean B1. This one is eally annoying, I'm hoping someone has seen this before. Vehicle came in about 6 months ago with a catalyist deficiency code. Hooked up the matco scanner graphed the B1S2 sensor and it was definitely getting too high a switch rate, so ordered a dir...
April 24, 2007
2000 Nissan Sentra GXE 1.8L Poor Idle Quality, Hesitation, Cuts out, Stall, MIL Lamp on VIN: 3N1CB51D6Y
P0171: Fuel Trim Lean. ... THIS CAR HAS BEEN TO 2 OTHER SHOPS AND THEY HAVE BOTH PUT FUEL PUMPS IN IT AND HAD NO EFFECT. FUEL PRESSURE READS RIGHT ON THE MONEY BUT IF YOU CLAMP OFF THE RETURN LINE BOOSTING THE PRESSURE TO ABOUT 110PSI THE CAR RUNS PERFECT, OTHERWISE YOU CAN BARELY G...
April 25, 2007
1998 Ford F-150 4.6L Poor Fuel Economy VIN: 2FT2X1769W
P0171: system too lean bank1. keeps reapeating same codes cant find a problem i know these fords r bad about intake plenum leaks but smoked it with no avail any help would be much appreciated
April 26, 2007
1997 Mercedes-Benz E320 3.2L No Start VIN: WDFJF55F2V
P0171: Bank 1 lean condition. Does anyone have any information on how to test the idle control system? There is a control module under the throttle pedal, and in the intake. This engine will run when an alternative fuel source is introduced. (I.e. starting fluid) Will not stay running.
April 29, 2007
2000 Toyota Solara SE 3.0L MIL Lamp on VIN: 2T1CF22P7Y
P0171: System lean Bank 1. ... failing at a smog station. After testing we changed the B1S1 O2 sensor and MAF sensor. We are still getting a code P0171 after resetting the monitors. Sometimes it will set all the monitors without setting the code. Then, next startup the light will come o...
April 03, 2007
1996 Chevrolet Cavalier Z24 2.4L Misfire, MIL Lamp on VIN: 1G1JF12T1T
P0171: Fuel System Lean (Bank 1). ... car will run great sometimes for hours or days then out of the blue starts misfiring backfiring pooring black smoke then next time you start engine it may run fine or not. ckp \cmp signal ok codes p0171 lean bank 1\p0300 m...
April 04, 2007
2001 Ford Focus ZX3 2.0L MIL Lamp on VIN: 3FAFP31391
P0171: lean bank 1. ... it has been in my shop on and off for the past year with the same code P0171. My long term fuel trim is around 25% and the short is about .3 +/-. It has has a new o2 sensor, mass air flow, fuel pump (at the dealer) I replaced egr last time for a seperate i...
April 04, 2007
2001 Ford F-150 XL 4.2L MIL Lamp on VIN: 1FTZF17221
P0171: bank 1 lean condition. ... engine light on. The code was p0171 (lean condition bank 1). Typically on these Fords we followed the service bulletin for the upper intake manifold gaskets internally leaking. We changed all seals, gaskets and pcv valve and cleaned everything up. The cust...
April 05, 2007
2002 Ford Windstar LX 3.8L MIL Lamp on VIN: 2FMZA51472
P0171: lean condition bank 1. ... plain stumping me. It came from the used car lot we sublet for. originally we found 10 dtcs stored and found 4 issues. we replaced the lower intake manifold due to a vacuum leak around imrc shaft, we found it with smoke. bank 1 o2 for no operation. after t...
April 05, 2007
2001 Isuzu Rodeo LS 3.2L Hesitation, Stall, MIL Lamp on VIN: 4S2DM58W61
P0171: Fuel System Too Lean (Bank 1). at 1,500 or 2,500 ltft = + 22 all o2's less than 100 mv fuel pressure = 47 passes noid light test passes injector pressure drop test maf looks good on the lab scope i need some ideas on what to test next
April 05, 2007
2000 Nissan Sentra SE 2.0L Hesitation VIN: 3N1BB51D8Y
P0171: Fuel Trim Lean. We have this Sentra with a P0171 Code. Looking at other Nissans on IATN looks like 99% of the cause is a bad MAF sensor. We tested it according to All Data and at 2500 rpm we got about 1.35 volts and at 4000 rpm 1.89 volts. Never got above 2.5 volts when revvi...
April 06, 2007
1995 Chevrolet S10 LS 4.3L Poor Idle Quality, Hesitation, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1GCCS19Z3S
P0171: Exaust Lean. ... The customer changed IAC, TPS, O2, no change. I pluged in my scan tool (Mastertech) and noticed iregular data stream, like system voltage droping to 2.4v or a RPM reeding of 99999, and code 55 amoung others. I checked all powers and grounds, and all the so...
April 12, 2007
1999 Ford Explorer XL 4.0L MIL Lamp on VIN: 1FMZ34X6XV
P0171: ltft. The car came mising codes in ECM P0171 P0174 LTFT lean [...]. Tune up and wire intake manfold uper and lower replace mass. car came back p0171 p0174 ltft# 5 to 10%.
April 16, 2007
2000 Nissan Maxima GLE 3.0L MIL Lamp on, Hard to start VIN: JN1CA31A8Y
P0171: Fuel Trim Lean (Bank 1). I know some Nissans like to have injector failures and I'm not sure if this car has the same common issue. I do not get rough running myself here but the customer is complaining about rough start up. I recently replaced the throttle body o-ring which was allow...
April 17, 2007
2001 BMW 525i 2.5L MIL Lamp on VIN: WBADT43481
P0171: Bank 1 lean. Alright, this one is bugging the hell out of me. Got this 01 BMW with lean codes. Runs fine with plenty of zip in it. Fuel trims are as follows: idle-STFT 8% LTFT 10% (both banks) cruise-switching bewteen -3% to 4% LTFT 8%. 02's switching nice. Fuel pressure g...
April 18, 2007
2001 Volkswagen Passat GLS 1.8L MIL Lamp on VIN: WVWPD63B61
P0171: system lean bank 1. ... light on with a code p0171 system lean bank #1. Car was in six months ago for the same code we installed a MAF sensor all was well until now. Car runs good, checked car for vacuume leaks none were found. Cleand throtle body light came back on. I saw some o...
April 19, 2007
1999 Chevrolet Camaro 3.8L Misfire, MIL Lamp on VIN: 2G1FP22K7X
P0171: Fuel Trim System Lean (Bank 1). THIS FOR A CO-WORKER,.. original complaint was no heat,..intake gasket was leaking,.NO driveability problems at that time. Replaced gaskets,..delivered car 3 days later check engine light on,..idles good when cold,..as engine warms up noticeable "shake"...
April 24, 2007
2001 Volkswagen Jetta GLS 2.0L MIL Lamp on VIN: 3VWSB69M01
P0171: System lean B1. This one is eally annoying, I'm hoping someone has seen this before. Vehicle came in about 6 months ago with a catalyist deficiency code. Hooked up the matco scanner graphed the B1S2 sensor and it was definitely getting too high a switch rate, so ordered a dir...
April 24, 2007
2000 Nissan Sentra GXE 1.8L Poor Idle Quality, Hesitation, Cuts out, Stall, MIL Lamp on VIN: 3N1CB51D6Y
P0171: Fuel Trim Lean. ... THIS CAR HAS BEEN TO 2 OTHER SHOPS AND THEY HAVE BOTH PUT FUEL PUMPS IN IT AND HAD NO EFFECT. FUEL PRESSURE READS RIGHT ON THE MONEY BUT IF YOU CLAMP OFF THE RETURN LINE BOOSTING THE PRESSURE TO ABOUT 110PSI THE CAR RUNS PERFECT, OTHERWISE YOU CAN BARELY G...
April 25, 2007
1998 Ford F-150 4.6L Poor Fuel Economy VIN: 2FT2X1769W
P0171: system too lean bank1. keeps reapeating same codes cant find a problem i know these fords r bad about intake plenum leaks but smoked it with no avail any help would be much appreciated
April 26, 2007
1997 Mercedes-Benz E320 3.2L No Start VIN: WDFJF55F2V
P0171: Bank 1 lean condition. Does anyone have any information on how to test the idle control system? There is a control module under the throttle pedal, and in the intake. This engine will run when an alternative fuel source is introduced. (I.e. starting fluid) Will not stay running.
April 29, 2007