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P0171 Diagnostic Trouble Code Discussion for May 2005

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
1999 Toyota 4Runner Limited 3.4L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on
P0171: Fuel System Too Lean (Bank 1). The truck idles a little rough. The fuel pressure readings at idle are excessive 44psi_=+ AND here's the deal, lt fuel is way off, almost to 40 at idle. when your cruising around, it tends to improve. However, looking at the vac diagram on the hood, which matc...
May 05, 2005
2001 Ford Explorer Eddie Bauer 4.0L MIL Lamp on VIN: 1FMZU74E91
P0171: Lean reading Bank 1. ... continuing to set both a P0171 & P0174, which refers to a lean condition at both bank one and two. Both oxygen sensors seem to be switching correctly (we still replaced oxygen sensors to be sure that sensors were not contaminated from the head gasket f...
May 10, 2005
1995 Ford Mustang 3.8L MIL Lamp on VIN: 1FALP4044S
P0171: lean bank 1. ... our building and is getting very frustrating for us and her. We have had the car in several times, originally for emissions falure due to MIL illuminated. Had lean codes, needed tune parts, etc. so we replaced all tune parts, cleaned injectors and intake s...
May 11, 2005
1999 Lexus ES300 3.0L MIL Lamp on VIN: JT8BF28G7X
P0171: Fuel System Too Lean (Bank 1). ... codes po325 knock sensor bank one, p0330 knock sensor bank 2, p0420 cat efficency , p0171 lean exhaust bank one and two misfire codes, Two coil packs were replaced, both knock sensors and both upsteam oxygen sensors were replaced. The only code that has co...
May 11, 2005
2000 Mazda 626 ES 2.0L MIL Lamp on VIN: 1YVGF22C3Y
P0171: Adaptive Fuel Trim Too Lean (Bank 1). Vehicle runs perfectly under all conditions, but the MIL troubles the customer. Troubleshooting the "lean bank 1" code, I found no vacuum leaks, fuel pressure is as specified, and all fuel parameters scanned properly. On only a hunch, I replaced the ma...
May 11, 2005
2000 Toyota Echo 1.5L Poor Idle Quality, Hesitation, Misfire, MIL Lamp on VIN: JTDBT1238Y
P0171: Fuel System Too Lean (Bank 1). Vehicle came in with P0171 code set and long crank times. Battery went dead due to key left on and then vehicle would barely run. Vehicle acted like plugged exhaust and would not accel over 25 MPH. Cat was extremely hot. Exhaust checked for plugging; nothing f...
May 12, 2005
1999 Toyota RAV4 2.0L Hesitation, MIL Lamp on VIN: JT3HP10V0X
P0171: Fuel System Too Lean (Bank 1). vehical sets po171 slight hesitation on accell fuel press and vol ok no vac leaks has calif emissions and utilizes an air fuel sensor that hangs around .590 and will not go beyond .500 and .690 should this air fuel sensor swing from .0 to .9 like a conventiona...
May 19, 2005
2002 Ford Escort SE 2.0L MIL Lamp on VIN: 3FAFP13P2R
P0171: system lean bank 1. no vacuum leaks,02 sensors repl,plugs good,pcv good,fuel pressure ok,injectors good, mass air flow sensors ok, seems all thats left is the computer, help
May 22, 2005
2002 Chevrolet Express 1500 5.7L Cuts out VIN: 1GBFG15R4Y
P0171: Fuel Trim System Lean (Bank 1). Hello ,thanks in advance.The van has no power while driving.I have made 1 road test that van dove great.If i give any gas to accel the injector pulse drops to 0.vehicle speed is correct.mass air seems ok.I have done complete tune up,cleaned maf and injectors.I...
May 24, 2005
2000 Nissan Maxima GLE 3.0L Hesitation, Surge, Stall, MIL Lamp on VIN: JN1CA31D2Y
P0171: Fuel Trim Lean (Bank 1). Im stuck on this one. I had done a wave form on maf, it appears to be doing its job. Although if you goose the throttle at idle guickly it will surge and stall. The B1 O2 seems to be toggling at an acceptable rate as well. I cleaned the carbon out of the throt...
May 24, 2005
2002 Chevrolet Express 1500 5.7L Cuts out VIN: 1GBFG15R4Y
P0171: Fuel Trim System Lean (Bank 1). Hello ,thanks in advance.The van has no power while driving.I have made 1 road test that van dove great.If i give any gas to accel the injector pulse drops to 0.vehicle speed is correct.mass air seems ok.I have done complete tune up,cleaned maf and injectors.I...
May 25, 2005
1999 Toyota 4Runner Limited 3.4L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on
P0171: Fuel System Too Lean (Bank 1). The truck idles a little rough. The fuel pressure readings at idle are excessive 44psi_=+ AND here's the deal, lt fuel is way off, almost to 40 at idle. when your cruising around, it tends to improve. However, looking at the vac diagram on the hood, which matc...
May 05, 2005
2001 Ford Explorer Eddie Bauer 4.0L MIL Lamp on VIN: 1FMZU74E91
P0171: Lean reading Bank 1. ... continuing to set both a P0171 & P0174, which refers to a lean condition at both bank one and two. Both oxygen sensors seem to be switching correctly (we still replaced oxygen sensors to be sure that sensors were not contaminated from the head gasket f...
May 10, 2005
1995 Ford Mustang 3.8L MIL Lamp on VIN: 1FALP4044S
P0171: lean bank 1. ... our building and is getting very frustrating for us and her. We have had the car in several times, originally for emissions falure due to MIL illuminated. Had lean codes, needed tune parts, etc. so we replaced all tune parts, cleaned injectors and intake s...
May 11, 2005
1999 Lexus ES300 3.0L MIL Lamp on VIN: JT8BF28G7X
P0171: Fuel System Too Lean (Bank 1). ... codes po325 knock sensor bank one, p0330 knock sensor bank 2, p0420 cat efficency , p0171 lean exhaust bank one and two misfire codes, Two coil packs were replaced, both knock sensors and both upsteam oxygen sensors were replaced. The only code that has co...
May 11, 2005
2000 Mazda 626 ES 2.0L MIL Lamp on VIN: 1YVGF22C3Y
P0171: Adaptive Fuel Trim Too Lean (Bank 1). Vehicle runs perfectly under all conditions, but the MIL troubles the customer. Troubleshooting the "lean bank 1" code, I found no vacuum leaks, fuel pressure is as specified, and all fuel parameters scanned properly. On only a hunch, I replaced the ma...
May 11, 2005
2000 Toyota Echo 1.5L Poor Idle Quality, Hesitation, Misfire, MIL Lamp on VIN: JTDBT1238Y
P0171: Fuel System Too Lean (Bank 1). Vehicle came in with P0171 code set and long crank times. Battery went dead due to key left on and then vehicle would barely run. Vehicle acted like plugged exhaust and would not accel over 25 MPH. Cat was extremely hot. Exhaust checked for plugging; nothing f...
May 12, 2005
1999 Toyota RAV4 2.0L Hesitation, MIL Lamp on VIN: JT3HP10V0X
P0171: Fuel System Too Lean (Bank 1). vehical sets po171 slight hesitation on accell fuel press and vol ok no vac leaks has calif emissions and utilizes an air fuel sensor that hangs around .590 and will not go beyond .500 and .690 should this air fuel sensor swing from .0 to .9 like a conventiona...
May 19, 2005
2002 Ford Escort SE 2.0L MIL Lamp on VIN: 3FAFP13P2R
P0171: system lean bank 1. no vacuum leaks,02 sensors repl,plugs good,pcv good,fuel pressure ok,injectors good, mass air flow sensors ok, seems all thats left is the computer, help
May 22, 2005
2002 Chevrolet Express 1500 5.7L Cuts out VIN: 1GBFG15R4Y
P0171: Fuel Trim System Lean (Bank 1). Hello ,thanks in advance.The van has no power while driving.I have made 1 road test that van dove great.If i give any gas to accel the injector pulse drops to 0.vehicle speed is correct.mass air seems ok.I have done complete tune up,cleaned maf and injectors.I...
May 24, 2005
2000 Nissan Maxima GLE 3.0L Hesitation, Surge, Stall, MIL Lamp on VIN: JN1CA31D2Y
P0171: Fuel Trim Lean (Bank 1). Im stuck on this one. I had done a wave form on maf, it appears to be doing its job. Although if you goose the throttle at idle guickly it will surge and stall. The B1 O2 seems to be toggling at an acceptable rate as well. I cleaned the carbon out of the throt...
May 24, 2005
2002 Chevrolet Express 1500 5.7L Cuts out VIN: 1GBFG15R4Y
P0171: Fuel Trim System Lean (Bank 1). Hello ,thanks in advance.The van has no power while driving.I have made 1 road test that van dove great.If i give any gas to accel the injector pulse drops to 0.vehicle speed is correct.mass air seems ok.I have done complete tune up,cleaned maf and injectors.I...
May 25, 2005