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P0171 Diagnostic Trouble Code Discussion for November 2004

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
1996 Chevrolet Express 1500 4.3L Stall, MIL Lamp on VIN: 1GCFG15W4T
P0171: Fuel Trim System Lean (Bank 1). If you start this van up it will start and run good. after a minute or two it will slowly start to bog and loose power. If I add propane the motor perks right up. Once it goes into closed loop the problem goes away. My gut tells me to replace the fuel pump. Bu...
November 05, 2004
1999 Ford Windstar LX 3.8L MIL Lamp on VIN: 2FMZA5141X
P0171: lean bank 1. looked for obvious problems and none found... i am at a loss here as to what is next to look for... heard that possible plastic intake problems... thanks in advance for any help
November 07, 2004
1999 Mazda B4000 SE 4.0L MIL Lamp on VIN: 4F4ZR17X9X
P0171: Adaptive Fuel Trim Too Lean (Bank 1). The customer brought this vehical in becuase the "check engine" light was on. With my scanner hooked up, the readings on the scanner, for the forward O2 sensors was showing that they were not functioning properly. At times the readings would stay at 0V...
November 08, 2004
2001 Nissan Pathfinder LE 3.5L Hesitation, MIL Lamp on VIN: JN8DR07Y61
P0171: Fuel Trim Lean (Bank 1). ... About one month ago, the truck came in with a P0171 code in it. I went through the troubleshooter in the Snap-on Scanner, and read the fixes here on IATN, and cleaned the MAF sensor. The fuel trim (ALPHA %) came back down to the under 105% (about 95%, and ...
November 08, 2004
1996 Jeep Grand Cherokee Laredo 4.0L No Start, Stall, dies while driving VIN: 1J4FX5835T
P0171: Fuel System Lean (Bank 1). This one has bugged me for a while, the only problem is that its so intermitten that it happens once a week or on long trips that exceed 75 miles. I am going on what the customer is relating to me. Basicaly he drives alot of long distances and the vehicle will...
November 09, 2004
1999 Mazda B4000 SE 4.0L MIL Lamp on VIN: 4F4ZR17X9X
P0171: Adaptive Fuel Trim Too Lean (Bank 1). The customer brought this vehical in becuase the "check engine" light was on. With my scanner hooked up, the readings on the scanner, for the forward O2 sensors was showing that they were not functioning properly. At times the readings would stay at 0V...
November 09, 2004
2000 Ford Focus LX 2.0L Stall, MIL Lamp on VIN: 1FAFP33PXY
P0171: System lean. ... needed help but this is the Boss' daughters car and of course it's not gonna give me a break hear it goes. This one came in w/ a reoccurring lean code this time it had a p1100 Maf curcuit problem. I suspect that the Maf problem might be whats causing my le...
November 10, 2004
2000 Ford Focus LX 2.0L Stall, MIL Lamp on VIN: 1FAFP33PXY
P0171: System lean. ... needed help but this is the Boss' daughters car and of course it's not gonna give me a break hear it goes. This one came in w/ a reoccurring lean code this time it had a p1100 Maf curcuit problem. I suspect that the Maf problem might be whats causing my le...
November 11, 2004
2000 Ford E-250 Econoline 5.4L MIL Lamp on VIN: 1FTNE24L9T
P0171: system lean bank 1. vehicle came in with check engine light on setting codes po171 and 174 system lean banks 1 and 2.found maf not swiching properly.maf was replaced and codes reset.customer took vehicle and next day check engine light back on same codes.checked for vacuum leaks ...
November 16, 2004
1997 Lincoln Town Car Cartier 4.6L MIL Lamp on VIN: 1LNLM83W1V
... and I'm at my wits end Code P0171 and P0174 keeps coming back We have done all the flow chart diagnostics and have replaced all 0/2 sensors,Changed the EGR checked the passages and Smoke checked the engine with no luck.Our fuel pressure is running @ 28# th...
November 16, 2004
1997 Mercury Mystique GS 2.0L Poor Idle Quality, Surge, Stall, MIL Lamp on VIN: 1MELM6536V
P0171: system lean bank 1. after codes erased, only lean code returned once. idle is erratic and surges, sometimes stalls, worse with defrost ac on. Cannot find throttle body plate position adjustment as someone has been there before, also maf wiring has been cut and plug replaced. Vehi...
November 16, 2004
1996 Chevrolet Express 1500 4.3L Stall, MIL Lamp on VIN: 1GCFG15W4T
P0171: Fuel Trim System Lean (Bank 1). If you start this van up it will start and run good. after a minute or two it will slowly start to bog and loose power. If I add propane the motor perks right up. Once it goes into closed loop the problem goes away. My gut tells me to replace the fuel pump. Bu...
November 18, 2004
1998 Ford Windstar GL 3.8L MIL Lamp on VIN: 2FMZA5144W
P0171: system too lean bank 1. thanks to all in advance, this windstar once in a while will set the above mentioned codes with no drivabillity issues, so the first time it came in we scaned and did a visual under the hood, we found the pcv hose in bad shape and leaking, so that was fixed an...
November 18, 2004
1996 Ford E-250 Econoline 4.9L MIL Lamp on VIN: 1FTFE24Y6T
P0171: system too lean B1. Hello all, We have a E250 with CEL illuminated. scanned codes PO171 & PO174. American cars are not my forte and whant to get a heads up on what to look out for and check on this vehical. From these codes I would probably assume this vehical has a vac leak ...
November 24, 2004
2001 Nissan Sentra GXE 1.8L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 3N1CB51D41
P0171: Fuel Trim Lean. occurs in open loop and closed loop random misfiring at idle intermittently, unplugging individual coils all cylinders change engine running when opening the throttle sometimes rpm increases normally then next time could just bog out at 1500 rpm and if you hol...
November 24, 2004
2000 Volkswagen Golf GL 2.0L No Start VIN: WVWGC31J5X
P0171: fuel trim bnk 1. the car came in for hard start only after initial fill up of gas.it will start every time after. checked for code found the one listed checked fuel pressure and for vacuume leaks replaced vac hose to fuel pressure regulator and retested system all was good or ...
November 26, 2004
1996 Chevrolet Express 1500 4.3L Stall, MIL Lamp on VIN: 1GCFG15W4T
P0171: Fuel Trim System Lean (Bank 1). If you start this van up it will start and run good. after a minute or two it will slowly start to bog and loose power. If I add propane the motor perks right up. Once it goes into closed loop the problem goes away. My gut tells me to replace the fuel pump. Bu...
November 05, 2004
1999 Ford Windstar LX 3.8L MIL Lamp on VIN: 2FMZA5141X
P0171: lean bank 1. looked for obvious problems and none found... i am at a loss here as to what is next to look for... heard that possible plastic intake problems... thanks in advance for any help
November 07, 2004
1999 Mazda B4000 SE 4.0L MIL Lamp on VIN: 4F4ZR17X9X
P0171: Adaptive Fuel Trim Too Lean (Bank 1). The customer brought this vehical in becuase the "check engine" light was on. With my scanner hooked up, the readings on the scanner, for the forward O2 sensors was showing that they were not functioning properly. At times the readings would stay at 0V...
November 08, 2004
2001 Nissan Pathfinder LE 3.5L Hesitation, MIL Lamp on VIN: JN8DR07Y61
P0171: Fuel Trim Lean (Bank 1). ... About one month ago, the truck came in with a P0171 code in it. I went through the troubleshooter in the Snap-on Scanner, and read the fixes here on IATN, and cleaned the MAF sensor. The fuel trim (ALPHA %) came back down to the under 105% (about 95%, and ...
November 08, 2004
1996 Jeep Grand Cherokee Laredo 4.0L No Start, Stall, dies while driving VIN: 1J4FX5835T
P0171: Fuel System Lean (Bank 1). This one has bugged me for a while, the only problem is that its so intermitten that it happens once a week or on long trips that exceed 75 miles. I am going on what the customer is relating to me. Basicaly he drives alot of long distances and the vehicle will...
November 09, 2004
1999 Mazda B4000 SE 4.0L MIL Lamp on VIN: 4F4ZR17X9X
P0171: Adaptive Fuel Trim Too Lean (Bank 1). The customer brought this vehical in becuase the "check engine" light was on. With my scanner hooked up, the readings on the scanner, for the forward O2 sensors was showing that they were not functioning properly. At times the readings would stay at 0V...
November 09, 2004
2000 Ford Focus LX 2.0L Stall, MIL Lamp on VIN: 1FAFP33PXY
P0171: System lean. ... needed help but this is the Boss' daughters car and of course it's not gonna give me a break hear it goes. This one came in w/ a reoccurring lean code this time it had a p1100 Maf curcuit problem. I suspect that the Maf problem might be whats causing my le...
November 10, 2004
2000 Ford Focus LX 2.0L Stall, MIL Lamp on VIN: 1FAFP33PXY
P0171: System lean. ... needed help but this is the Boss' daughters car and of course it's not gonna give me a break hear it goes. This one came in w/ a reoccurring lean code this time it had a p1100 Maf curcuit problem. I suspect that the Maf problem might be whats causing my le...
November 11, 2004
2000 Ford E-250 Econoline 5.4L MIL Lamp on VIN: 1FTNE24L9T
P0171: system lean bank 1. vehicle came in with check engine light on setting codes po171 and 174 system lean banks 1 and 2.found maf not swiching properly.maf was replaced and codes reset.customer took vehicle and next day check engine light back on same codes.checked for vacuum leaks ...
November 16, 2004
1997 Lincoln Town Car Cartier 4.6L MIL Lamp on VIN: 1LNLM83W1V
... and I'm at my wits end Code P0171 and P0174 keeps coming back We have done all the flow chart diagnostics and have replaced all 0/2 sensors,Changed the EGR checked the passages and Smoke checked the engine with no luck.Our fuel pressure is running @ 28# th...
November 16, 2004
1997 Mercury Mystique GS 2.0L Poor Idle Quality, Surge, Stall, MIL Lamp on VIN: 1MELM6536V
P0171: system lean bank 1. after codes erased, only lean code returned once. idle is erratic and surges, sometimes stalls, worse with defrost ac on. Cannot find throttle body plate position adjustment as someone has been there before, also maf wiring has been cut and plug replaced. Vehi...
November 16, 2004
1996 Chevrolet Express 1500 4.3L Stall, MIL Lamp on VIN: 1GCFG15W4T
P0171: Fuel Trim System Lean (Bank 1). If you start this van up it will start and run good. after a minute or two it will slowly start to bog and loose power. If I add propane the motor perks right up. Once it goes into closed loop the problem goes away. My gut tells me to replace the fuel pump. Bu...
November 18, 2004
1998 Ford Windstar GL 3.8L MIL Lamp on VIN: 2FMZA5144W
P0171: system too lean bank 1. thanks to all in advance, this windstar once in a while will set the above mentioned codes with no drivabillity issues, so the first time it came in we scaned and did a visual under the hood, we found the pcv hose in bad shape and leaking, so that was fixed an...
November 18, 2004
1996 Ford E-250 Econoline 4.9L MIL Lamp on VIN: 1FTFE24Y6T
P0171: system too lean B1. Hello all, We have a E250 with CEL illuminated. scanned codes PO171 & PO174. American cars are not my forte and whant to get a heads up on what to look out for and check on this vehical. From these codes I would probably assume this vehical has a vac leak ...
November 24, 2004
2001 Nissan Sentra GXE 1.8L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 3N1CB51D41
P0171: Fuel Trim Lean. occurs in open loop and closed loop random misfiring at idle intermittently, unplugging individual coils all cylinders change engine running when opening the throttle sometimes rpm increases normally then next time could just bog out at 1500 rpm and if you hol...
November 24, 2004
2000 Volkswagen Golf GL 2.0L No Start VIN: WVWGC31J5X
P0171: fuel trim bnk 1. the car came in for hard start only after initial fill up of gas.it will start every time after. checked for code found the one listed checked fuel pressure and for vacuume leaks replaced vac hose to fuel pressure regulator and retested system all was good or ...
November 26, 2004