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P0171 Diagnostic Trouble Code Discussion for January 2007

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2001 GMC Sierra 1500 SL 4.8L Poor Idle Quality, Misfire VIN: 2GTEC19V51
P0171: Fuel Trim System Lean (Bank 1). ... it came in and had a P0171 and P0174 lean codes... sprayed carb cleaner around looking for a vacum leak and noticed my long term seemed to change when I soaked the intake runner so I tr...
January 03, 2007
2001 GMC Sierra 1500 SL 4.8L Poor Idle Quality, Misfire VIN: 2GTEC19V51
P0171: Fuel Trim System Lean (Bank 1). ... it came in and had a P0171 and P0174 lean codes... sprayed carb cleaner around looking for a vacum leak and noticed my long term seemed to change when I soaked the intake runner so I tr...
January 04, 2007
1999 Lexus RX300 3.0L Excessive Emissions, Misfire, MIL Lamp on VIN: JT6HF10U3X
P0171: bank 1 system lean. Hey all, I have this Lexus RX300 that have been giving me a problem. This vehicle seems to only show problem in Bank 1 with the emission system. Bank 1 LT fuel trim is at 52.3% while bank 2 is pretty normal at 8.5%. Spark plugs been changed and yet still exhib...
January 05, 2007
2003 Toyota Corolla CE 1.8L Surge, MIL Lamp on VIN: 1NXBR32E43
P0171: Fuel System Too Lean (Bank 1). ... anywhere on, this is a car that we just bought at auction so previous history is unknown. Mil illuminated, when cold the idle will surge at times, when hot the surge is not as pronounced but is still there intermittantly, Found P0171 and thought this is ea...
January 07, 2007
1997 Ford Explorer XL 4.0L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on VIN: 1FMDU34X5V
P0171: system lean bank 1. ... OTHER SHOPS, CAME IN WITH CHECK ENGINE LIGHT ON AND POOR GAS MILEAGE COMPLAINT. CUSTOMER HAS BEEN TO SEVERAL OTHER SHOPS THEY HAVE REPLACED MAF,O2 SENSORS,INTAKE MANIFOLD GASKETS, PCM BEEN REFLASHED, CAR HAS BEEN SMOKED AND NO LEAKS FOUND, FUEL PRESSURE HA...
January 09, 2007
2004 Ford Taurus SE 3.0L No Start, Poor Idle Quality, MIL Lamp on VIN: 1FAHP53U14
P0171: Bank 1 lean. Car will start and barely run at half throttle. Carb spray will keep it running at closed throttle. I have spark, injector pulse, and my fuel pressure seems to vary between 40 and 60psi. Spark plugs and fuel filter were original, spark plugs fouled but too muc...
January 10, 2007
1999 Ford Windstar LX 3.8L MIL Lamp on VIN: 2FMZA5142X
P0171: bank 1 lean. ... mil lamp was on, same two codes p0171 p0174. fuel pressure was good, but flow was bad. fuel filter was plugged (had the original). checked for vacuum leaks and egr function. all appear ok. no codes for injector malfunction. is this about the right time for...
January 13, 2007
2002 Chevrolet Venture LS 3.4L Surge VIN: 1GNDUO3E32
P0171: Fuel Trim System Lean (Bank 1). Hi guys, I've got one here thats kicking my butt. Customer brought vehicle in stating that it failed emmission testing. The first thing I noticed is that someone has removed the check engine light bulb. Vehicle has slight surge at idle. Scanned for codes (see ...
January 15, 2007
1996 Ford Windstar GL 3.8L Poor Idle Quality, Surge, Erratic High Idle VIN: 2FMDA5148T
P0171: Lean Bank 1. Car came to us with high erratic idle. Customer was told somewhere else that it was a major vacuum leak. Pulled upper plenum to inspect, found everything okay, EGR ports clear, nothing noted with manifold runners (linkages good, not excessive buildup at plates...
January 18, 2007
1998 Ford E-250 Econoline 4.2L MIL Lamp on VIN: 1FTPE1429W
P0171: bank 1 system lean. Long term fuel trims are both at 25% and short term are mid teens at Idle or high idle. Driving vehicle under load long terms are 5 to 7 and short terms fluctuate +/-, but as soon as you let up or maintain cruising speed long terms return to 25%. Bleeding prop...
January 18, 2007
2001 Ford E-150 Econoline 4.2L MIL Lamp on VIN: 1FTRE14201
P0171: Lean Bank. When I got this the mil light is on with code po 171 and po 174 Fuel pressure is good so I immediately check for vacuum leaks with a propane sniffer and checked the manifold as well as the pcv connections and found no leaks, Even used carb cleaner but no leaks...
January 18, 2007
1995 Lincoln Continental Diamond Anniversary 4.6L MIL Lamp on VIN: 1LNLM97V2S
P0171: lean bank 1. hey guys,this one is strange.blowing lean codes,short term fuel trim pegged at 25%.long term creeping right behind it everytime we reset the fuel trim.os sensors stay at .02v.at idle pulse width at 2.6ms.no vacuum leaks.current baro is 150(still a little low)i...
January 18, 2007
1998 Nissan Frontier 2.4L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1N6DD21S3W
P0171: Fuel Trim Lean (Bank 1). OK this one is taking alot of my time. Truck came in barely running under a load. checked fuel pressure would drop to 25 psi @ times, so I replaced the pump & filter. The truck then appeared to be fixed, however, after the air cleaner was put back on there...
January 18, 2007
2002 Ford F-150 King Ranch 4.6L Poor Idle Quality, Misfire, MIL Lamp on, no power VIN: 1FTRW07632
P0171: lean. Truck came in with no history. It is owned my local poilce. Was aquired threw drug deal. Trucks runs sluggish and misses. Cylinder head temp sensor is reading 392 degrees. Installed new cht sensor with no change. Tried different scanner with same results. Chec...
January 19, 2007
1998 Nissan Frontier 2.4L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1N6DD21S3W
P0171: Fuel Trim Lean (Bank 1). OK this one is taking alot of my time. Truck came in barely running under a load. checked fuel pressure would drop to 25 psi @ times, so I replaced the pump & filter. The truck then appeared to be fixed, however, after the air cleaner was put back on there...
January 19, 2007
1999 Oldsmobile Silhouette Premiere 3.4L Hesitation, Cuts out, Misfire VIN: 1GHDX03E3X
P0171: Fuel Trim System Lean (Bank 1). when vehicle fisrt came in it had no power under load and code 3x signal. replaced exhaust conveter and crank shaft sensors and test drove. vehicle ran fine for two days. now when engine is cold and vehicle is started and engine rpms up to 1500-3000 vehicle cu...
January 19, 2007
2002 Ford F-150 King Ranch 4.6L Poor Idle Quality, Misfire, MIL Lamp on, no power VIN: 1FTRW07632
P0171: lean. Truck came in with no history. It is owned my local poilce. Was aquired threw drug deal. Trucks runs sluggish and misses. Cylinder head temp sensor is reading 392 degrees. Installed new cht sensor with no change. Tried different scanner with same results. Chec...
January 22, 2007
1997 Buick LeSabre Custom 3.8L Stall, MIL Lamp on
P0171: Fuel System Lean. hello this vehicle runs fine most of the time, i got it to act up once w/ the maf unplugged the sft maxxed out & set the code at idle. i haven't been able to find any vacuum leaks.it seems to be electrical since it comes & goes at random.i have checked...
January 23, 2007
1997 Buick LeSabre Custom 3.8L Stall, MIL Lamp on
P0171: Fuel System Lean. hello this vehicle runs fine most of the time, i got it to act up once w/ the maf unplugged the sft maxxed out & set the code at idle. i haven't been able to find any vacuum leaks.it seems to be electrical since it comes & goes at random.i have checked...
January 25, 2007
1999 Ford Explorer XL 4.0L MIL Lamp on VIN: 1FMZU32XUB
P0171: system too lean bank 1. hey guys, the fuel trims are way off on this vehicle. the baro is reading good at 157hz. no vacuum leaks tried carb cleaner and smoke tester. also i was looking at the fuel trims while i was testing and they did not change.long term fuel trim is at 21 to 25.sh...
January 26, 2007
1998 Mazda Protege ES 1.8L MIL Lamp on VIN: JM1BJ2217X
P0171: System running too lean. ... Protege ES with the Check Engine Light on.The Scanner picked up code P0171. I tested the o2s they were within range.I cleaned the mass air flow sensor and reset the ecm.After two days the light came back on with the same code. I went to the dealer and get ...
January 26, 2007
2004 Ford F-150 Heritage XL 4.6L Poor Idle Quality, MIL Lamp on, NO POWER VIN: 2FTRX18W24
P0171: system too lean bank 1. ... acceleration. It hardly crawls up a hill. Two months ago we serviced this vehicle for a dead miss. At that time we had misfire codes along with lean running codes (P0171 & P0174). Replaced 2 injectors on Bank 1. Did a tune up w...
January 29, 2007
2001 Pontiac Grand Am SE 2.4L Poor Idle Quality, Hesitation, Cuts out, Misfire, MIL Lamp on VIN: 1G2NF52T71
P0171: Fuel System Lean. ... tune-up with OE parts and fuel pump and filter replaced. The problem is that it has a constant lean run condition with trouble code P0171. If I remove a vacuum line and try to lean it out further the 02 sensor volts climb to .800 range instead of dropping....
January 29, 2007
2000 Ford Explorer XLT 4.0L MIL Lamp on VIN: 1FMZU73X8Y
P0171: Bank-1 Lean. Very confused on this one. Code P0171 & 0174 stored. Fuel trims are perfect. No tsb's on re-flashing. Freeze frame failure records show that fuel trims are at 25 when codes set. Unable to recreate condition. No vacuum leaks found with the intake system( sm...
January 30, 2007
2003 Ford Windstar SE 3.8L MIL Lamp on VIN: 2FMZA52413
P0171: bank one lean. i have this windstar that i need help with, it keeps coming back with the po.171,po174, codes.{lean bank 1 and 2} i have replaced the upper intake orings and the vacum line for the fuel pressure regalator.. i have tryed fuel cleaner spray around the lower inta...
January 30, 2007
2003 Mazda 6 i 2.3L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 1YVFP80C73
P0171: Adaptive Fuel Trim Too Lean (Bank 1). this car has a bad hesitation, and hunts at idle, it doesnt appear to have any vacuum leaks and the maf readings look normal, (i ckleaned the maf sensor) i see the throttle chamber is totally electronic,no mechanical connection to throttle, is there something ...
January 31, 2007
2001 GMC Sierra 1500 SL 4.8L Poor Idle Quality, Misfire VIN: 2GTEC19V51
P0171: Fuel Trim System Lean (Bank 1). ... it came in and had a P0171 and P0174 lean codes... sprayed carb cleaner around looking for a vacum leak and noticed my long term seemed to change when I soaked the intake runner so I tr...
January 03, 2007
2001 GMC Sierra 1500 SL 4.8L Poor Idle Quality, Misfire VIN: 2GTEC19V51
P0171: Fuel Trim System Lean (Bank 1). ... it came in and had a P0171 and P0174 lean codes... sprayed carb cleaner around looking for a vacum leak and noticed my long term seemed to change when I soaked the intake runner so I tr...
January 04, 2007
1999 Lexus RX300 3.0L Excessive Emissions, Misfire, MIL Lamp on VIN: JT6HF10U3X
P0171: bank 1 system lean. Hey all, I have this Lexus RX300 that have been giving me a problem. This vehicle seems to only show problem in Bank 1 with the emission system. Bank 1 LT fuel trim is at 52.3% while bank 2 is pretty normal at 8.5%. Spark plugs been changed and yet still exhib...
January 05, 2007
2003 Toyota Corolla CE 1.8L Surge, MIL Lamp on VIN: 1NXBR32E43
P0171: Fuel System Too Lean (Bank 1). ... anywhere on, this is a car that we just bought at auction so previous history is unknown. Mil illuminated, when cold the idle will surge at times, when hot the surge is not as pronounced but is still there intermittantly, Found P0171 and thought this is ea...
January 07, 2007
1997 Ford Explorer XL 4.0L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on VIN: 1FMDU34X5V
P0171: system lean bank 1. ... OTHER SHOPS, CAME IN WITH CHECK ENGINE LIGHT ON AND POOR GAS MILEAGE COMPLAINT. CUSTOMER HAS BEEN TO SEVERAL OTHER SHOPS THEY HAVE REPLACED MAF,O2 SENSORS,INTAKE MANIFOLD GASKETS, PCM BEEN REFLASHED, CAR HAS BEEN SMOKED AND NO LEAKS FOUND, FUEL PRESSURE HA...
January 09, 2007
2004 Ford Taurus SE 3.0L No Start, Poor Idle Quality, MIL Lamp on VIN: 1FAHP53U14
P0171: Bank 1 lean. Car will start and barely run at half throttle. Carb spray will keep it running at closed throttle. I have spark, injector pulse, and my fuel pressure seems to vary between 40 and 60psi. Spark plugs and fuel filter were original, spark plugs fouled but too muc...
January 10, 2007
1999 Ford Windstar LX 3.8L MIL Lamp on VIN: 2FMZA5142X
P0171: bank 1 lean. ... mil lamp was on, same two codes p0171 p0174. fuel pressure was good, but flow was bad. fuel filter was plugged (had the original). checked for vacuum leaks and egr function. all appear ok. no codes for injector malfunction. is this about the right time for...
January 13, 2007
2002 Chevrolet Venture LS 3.4L Surge VIN: 1GNDUO3E32
P0171: Fuel Trim System Lean (Bank 1). Hi guys, I've got one here thats kicking my butt. Customer brought vehicle in stating that it failed emmission testing. The first thing I noticed is that someone has removed the check engine light bulb. Vehicle has slight surge at idle. Scanned for codes (see ...
January 15, 2007
1996 Ford Windstar GL 3.8L Poor Idle Quality, Surge, Erratic High Idle VIN: 2FMDA5148T
P0171: Lean Bank 1. Car came to us with high erratic idle. Customer was told somewhere else that it was a major vacuum leak. Pulled upper plenum to inspect, found everything okay, EGR ports clear, nothing noted with manifold runners (linkages good, not excessive buildup at plates...
January 18, 2007
1998 Ford E-250 Econoline 4.2L MIL Lamp on VIN: 1FTPE1429W
P0171: bank 1 system lean. Long term fuel trims are both at 25% and short term are mid teens at Idle or high idle. Driving vehicle under load long terms are 5 to 7 and short terms fluctuate +/-, but as soon as you let up or maintain cruising speed long terms return to 25%. Bleeding prop...
January 18, 2007
2001 Ford E-150 Econoline 4.2L MIL Lamp on VIN: 1FTRE14201
P0171: Lean Bank. When I got this the mil light is on with code po 171 and po 174 Fuel pressure is good so I immediately check for vacuum leaks with a propane sniffer and checked the manifold as well as the pcv connections and found no leaks, Even used carb cleaner but no leaks...
January 18, 2007
1995 Lincoln Continental Diamond Anniversary 4.6L MIL Lamp on VIN: 1LNLM97V2S
P0171: lean bank 1. hey guys,this one is strange.blowing lean codes,short term fuel trim pegged at 25%.long term creeping right behind it everytime we reset the fuel trim.os sensors stay at .02v.at idle pulse width at 2.6ms.no vacuum leaks.current baro is 150(still a little low)i...
January 18, 2007
1998 Nissan Frontier 2.4L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1N6DD21S3W
P0171: Fuel Trim Lean (Bank 1). OK this one is taking alot of my time. Truck came in barely running under a load. checked fuel pressure would drop to 25 psi @ times, so I replaced the pump & filter. The truck then appeared to be fixed, however, after the air cleaner was put back on there...
January 18, 2007
2002 Ford F-150 King Ranch 4.6L Poor Idle Quality, Misfire, MIL Lamp on, no power VIN: 1FTRW07632
P0171: lean. Truck came in with no history. It is owned my local poilce. Was aquired threw drug deal. Trucks runs sluggish and misses. Cylinder head temp sensor is reading 392 degrees. Installed new cht sensor with no change. Tried different scanner with same results. Chec...
January 19, 2007
1998 Nissan Frontier 2.4L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1N6DD21S3W
P0171: Fuel Trim Lean (Bank 1). OK this one is taking alot of my time. Truck came in barely running under a load. checked fuel pressure would drop to 25 psi @ times, so I replaced the pump & filter. The truck then appeared to be fixed, however, after the air cleaner was put back on there...
January 19, 2007
1999 Oldsmobile Silhouette Premiere 3.4L Hesitation, Cuts out, Misfire VIN: 1GHDX03E3X
P0171: Fuel Trim System Lean (Bank 1). when vehicle fisrt came in it had no power under load and code 3x signal. replaced exhaust conveter and crank shaft sensors and test drove. vehicle ran fine for two days. now when engine is cold and vehicle is started and engine rpms up to 1500-3000 vehicle cu...
January 19, 2007
2002 Ford F-150 King Ranch 4.6L Poor Idle Quality, Misfire, MIL Lamp on, no power VIN: 1FTRW07632
P0171: lean. Truck came in with no history. It is owned my local poilce. Was aquired threw drug deal. Trucks runs sluggish and misses. Cylinder head temp sensor is reading 392 degrees. Installed new cht sensor with no change. Tried different scanner with same results. Chec...
January 22, 2007
1997 Buick LeSabre Custom 3.8L Stall, MIL Lamp on
P0171: Fuel System Lean. hello this vehicle runs fine most of the time, i got it to act up once w/ the maf unplugged the sft maxxed out & set the code at idle. i haven't been able to find any vacuum leaks.it seems to be electrical since it comes & goes at random.i have checked...
January 23, 2007
1997 Buick LeSabre Custom 3.8L Stall, MIL Lamp on
P0171: Fuel System Lean. hello this vehicle runs fine most of the time, i got it to act up once w/ the maf unplugged the sft maxxed out & set the code at idle. i haven't been able to find any vacuum leaks.it seems to be electrical since it comes & goes at random.i have checked...
January 25, 2007
1999 Ford Explorer XL 4.0L MIL Lamp on VIN: 1FMZU32XUB
P0171: system too lean bank 1. hey guys, the fuel trims are way off on this vehicle. the baro is reading good at 157hz. no vacuum leaks tried carb cleaner and smoke tester. also i was looking at the fuel trims while i was testing and they did not change.long term fuel trim is at 21 to 25.sh...
January 26, 2007
1998 Mazda Protege ES 1.8L MIL Lamp on VIN: JM1BJ2217X
P0171: System running too lean. ... Protege ES with the Check Engine Light on.The Scanner picked up code P0171. I tested the o2s they were within range.I cleaned the mass air flow sensor and reset the ecm.After two days the light came back on with the same code. I went to the dealer and get ...
January 26, 2007
2004 Ford F-150 Heritage XL 4.6L Poor Idle Quality, MIL Lamp on, NO POWER VIN: 2FTRX18W24
P0171: system too lean bank 1. ... acceleration. It hardly crawls up a hill. Two months ago we serviced this vehicle for a dead miss. At that time we had misfire codes along with lean running codes (P0171 & P0174). Replaced 2 injectors on Bank 1. Did a tune up w...
January 29, 2007
2001 Pontiac Grand Am SE 2.4L Poor Idle Quality, Hesitation, Cuts out, Misfire, MIL Lamp on VIN: 1G2NF52T71
P0171: Fuel System Lean. ... tune-up with OE parts and fuel pump and filter replaced. The problem is that it has a constant lean run condition with trouble code P0171. If I remove a vacuum line and try to lean it out further the 02 sensor volts climb to .800 range instead of dropping....
January 29, 2007
2000 Ford Explorer XLT 4.0L MIL Lamp on VIN: 1FMZU73X8Y
P0171: Bank-1 Lean. Very confused on this one. Code P0171 & 0174 stored. Fuel trims are perfect. No tsb's on re-flashing. Freeze frame failure records show that fuel trims are at 25 when codes set. Unable to recreate condition. No vacuum leaks found with the intake system( sm...
January 30, 2007
2003 Ford Windstar SE 3.8L MIL Lamp on VIN: 2FMZA52413
P0171: bank one lean. i have this windstar that i need help with, it keeps coming back with the po.171,po174, codes.{lean bank 1 and 2} i have replaced the upper intake orings and the vacum line for the fuel pressure regalator.. i have tryed fuel cleaner spray around the lower inta...
January 30, 2007
2003 Mazda 6 i 2.3L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 1YVFP80C73
P0171: Adaptive Fuel Trim Too Lean (Bank 1). this car has a bad hesitation, and hunts at idle, it doesnt appear to have any vacuum leaks and the maf readings look normal, (i ckleaned the maf sensor) i see the throttle chamber is totally electronic,no mechanical connection to throttle, is there something ...
January 31, 2007