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P0171 Diagnostic Trouble Code Discussion for October 2007

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2002 Ford Ranger Edge 3.0L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on VIN: 1FTYR14U62
P0171: fuel system lean bank 1. ... sets p0171 and p0174 fuel lean dtc's, it has a slight rough idle, the ford dealer diagnoised this as a mass air flow and fuel filter issue, so customer brought to us and we replaced the items including plugs that were wo...
October 02, 2007
2000 Toyota Echo 1.5L MIL Lamp on, P0171 VIN: JTDAT1239Y
P0171: Fuel System Too Lean (Bank 1). vehicle had po171 cleared code roadtest code came back .checked data seems to run good any suggestions would help replaced upstream o2 still light came back on smoke tested intake for leaks seems ok
October 02, 2007
2003 Honda CR-V EX 2.4L MIL Lamp on VIN: JHLR78433C
P0171: Fuel System Too Lean (Bank 1). Po 171 comes up during idle... A/F reading is 1.20...According to tsb should be 1.00... Smoked system for vacuum leak... None found... Replaced MAP with new oem...P.s. there is a tsb about Map...Also tried a new A/F sensor A.K.A as oxygen sensor...(sensor read...
October 03, 2007
2000 Nissan Maxima GLE 3.0L MIL Lamp on VIN: JN1CA31D3Y
P0171: Fuel Trim Lean (Bank 1). Hi and 2000 Nissan Maxima. Runs/drives fine. Repeating codes PO171/PO174 system lean. Freeze frame shows several times that occurs at 47-52 mph. Thinking bad EGR or replace injectors/etc but really don`t know.
October 03, 2007
2002 Ford Focus ZTW 2.0L MIL Lamp on, Fuel trim VIN: 1FAHP36392
P0171: Lean Bank 1. This Focus is a well maintained (by me)vehicle. Check engine light came on, lean bank one. Performed a tune up checked for vaccum leaks (no smoke machine) and found a pipe to the very lower back of the intake possibly leaking. I sealed that up and drove the ve...
October 05, 2007
1997 Lincoln Town Car Signature 4.6L MIL Lamp on VIN: 1LNLM82W0V
P0171: system lean bank 1. ... to the Bosses sister. It has a the MIL on with codes P0171 and P0174 and has a hunting on start up and will go away after about three to five minutes. I have checked for vacuum leaks and fond none. I pulled the Mass Air Fl...
October 09, 2007
1997 Ford Ranger XLT 4.0L MIL Lamp on VIN: 1FTCR11X6V
P0171: system lean. Hello Group, This Ranger has these 2 codes stored. We have checked the usual suspects (MAF,Intake seal leaks,O2 sensors etc.) with no problem found. The O2 sensors are stuck on 0.0v and fuel trim is -100%. If I force the sensors with propane they still do not ...
October 12, 2007
2000 Ford Explorer XLT 4.0L MIL Lamp on VIN: 1FMZU73X2Y
P0171: Bank 1 system lean. AT IDLE bank2 long trim +10% bank1 LT -6 short trim 0% ST -2 AT 2500 RPM bank2 LT+11 BANK1 LT+11 SH 0 ST -8
October 13, 2007
2004 Audi A8 Quattro L 4.2L MIL Lamp on VIN: WAUML44E94
P0171: lean bank 1. Thanks for taking time to read this. Help all audi techs. This A8 came in for a regular oil change a couple days ago. Came back with above listed codes. Found hose for air pump disconnected from air box. reconnected hose cleared codes and sent it on its way. N...
October 15, 2007
2002 Ford Focus ZTW 2.0L MIL Lamp on, Fuel trim VIN: 1FAHP36392
P0171: Lean Bank 1. This Focus is a well maintained (by me)vehicle. Check engine light came on, lean bank one. Performed a tune up checked for vaccum leaks (no smoke machine) and found a pipe to the very lower back of the intake possibly leaking. I sealed that up and drove the ve...
October 15, 2007
1997 Jeep Grand Cherokee Laredo 4.0L Poor Idle Quality VIN: 1J4GZ58S9V
P0171: Fuel System Lean (Bank 1). ... (OEM) about 3 1/2 months ago the vehicle has come back 3 times with the same problem, engine has an unstable idle, runs rich, loss of power and ck. engine light on (P0171) after replacing the front oxygen sensor (2 after market and 1 OEM) the engine runs n...
October 17, 2007
2000 Chevrolet S10 4.3L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on VIN: 1GCCT19WXY
P0171: Fuel System Lean. 02 sensor stick on lean an bank i runs rich
October 19, 2007
2005 Ford Ranger Edge 3.0L Poor Idle Quality, MIL Lamp on VIN: 1FTYR10U65
P0171: Bank 1 system lean. ... ranger. It has a lean code p0171 and a slightly rough idle. ive smoke tested the intake hot, cold, in between and no leaks. Checked compression and engine vaccum thinking recessed valve seats but everything checks out ok. The MAF seems to be reading proper...
October 23, 2007
2002 GMC Sonoma SL 2.2L Poor Idle Quality, Surge, MIL Lamp on VIN: 1GTCS14582
P0171: Fuel System Lean. ... After firing it up it ran fine for 2 days and then started missing. Found an injector harness plug not fully seated. Good to go. Came back 1 week later with P0171- system too lean bank 1 code set and idle so high that owne...
October 24, 2007
1997 Toyota Camry CE 2.2L MIL Lamp on, Lacks Power VIN: 4T1BG22K5V
P0171: Fuel System Too Lean (Bank 1). ... Engine" light on - code P0171 lean condition. On a test drive it is a total slug under load - won't rev past 3,000 rpm at full throttle. Will get up to speed if you nurse the pedal. Fuel pressure 51 psi and remains good when symptons occur. Adding fue...
October 24, 2007
1999 Saab 9-3 2.0L Poor Fuel Economy, MIL Lamp on VIN: YS3DD58N6X
P0171: long term fuel trim fault. Vehicle presented with cel. Inspection revealed a failing map sensor. Replaced map sensor and cleared codes. Ok on our test drive. Cel came back on a couple of days after customer picked up, same codes. Customer reports gas mileage worse when cel is on. Smoke ...
October 25, 2007
2000 Toyota Tacoma DLX 3.4L MIL Lamp on VIN: 4TAWN72N3Y
P0171: Fuel System Too Lean (Bank 1). ... with code p0171, bank one too lean. another shop has already installed upstream oxygen sensor and fuel filter. fuel pressure is good, i've check for vacuum leaks with carb cleaner, propane, and a smoke machine. coolant temp sensor is reading correctly, o2 ...
October 25, 2007
2001 Lexus GS300 3.0L Hesitation VIN: JT8BD69S91
P0171: Fuel System Too Lean (Bank 1). I can not check fuel press. yet until the special fitting I order comes in,but I will update as soon as I can.This car came in with mil light on and code PO171 lean.Every thing looks good on a scanner except the maf reading is a little off at 2500 rpm's should...
October 29, 2007
1999 Toyota 4Runner Limited 3.4L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on VIN: JT3GN87ROX
P0171: Fuel System Too Lean (Bank 1). This 99 Toyota 4-Runner has a PO171 System lean code, fuel trim is going crazy, smoked the system, no leaks found, fuel pressure is good, no leaks in the air induction system, O2's are good, MAF tests good... Thanks in advance for your assistance. David
October 29, 2007
2001 Mazda Protege ES 2.0L Misfire, MIL Lamp on VIN: JM1BJ22591
P0171: Adaptive Fuel Trim Too Lean (Bank 1). hello all, i am dealing with a 2001 mazda protege that has an intermittent misfire that causes the engine to die or stumble. it has code p300 (random/multiple misfire). both of the coils check out fine.
October 31, 2007
2002 Ford Ranger Edge 3.0L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on VIN: 1FTYR14U62
P0171: fuel system lean bank 1. ... sets p0171 and p0174 fuel lean dtc's, it has a slight rough idle, the ford dealer diagnoised this as a mass air flow and fuel filter issue, so customer brought to us and we replaced the items including plugs that were wo...
October 02, 2007
2000 Toyota Echo 1.5L MIL Lamp on, P0171 VIN: JTDAT1239Y
P0171: Fuel System Too Lean (Bank 1). vehicle had po171 cleared code roadtest code came back .checked data seems to run good any suggestions would help replaced upstream o2 still light came back on smoke tested intake for leaks seems ok
October 02, 2007
2003 Honda CR-V EX 2.4L MIL Lamp on VIN: JHLR78433C
P0171: Fuel System Too Lean (Bank 1). Po 171 comes up during idle... A/F reading is 1.20...According to tsb should be 1.00... Smoked system for vacuum leak... None found... Replaced MAP with new oem...P.s. there is a tsb about Map...Also tried a new A/F sensor A.K.A as oxygen sensor...(sensor read...
October 03, 2007
2000 Nissan Maxima GLE 3.0L MIL Lamp on VIN: JN1CA31D3Y
P0171: Fuel Trim Lean (Bank 1). Hi and 2000 Nissan Maxima. Runs/drives fine. Repeating codes PO171/PO174 system lean. Freeze frame shows several times that occurs at 47-52 mph. Thinking bad EGR or replace injectors/etc but really don`t know.
October 03, 2007
2002 Ford Focus ZTW 2.0L MIL Lamp on, Fuel trim VIN: 1FAHP36392
P0171: Lean Bank 1. This Focus is a well maintained (by me)vehicle. Check engine light came on, lean bank one. Performed a tune up checked for vaccum leaks (no smoke machine) and found a pipe to the very lower back of the intake possibly leaking. I sealed that up and drove the ve...
October 05, 2007
1997 Lincoln Town Car Signature 4.6L MIL Lamp on VIN: 1LNLM82W0V
P0171: system lean bank 1. ... to the Bosses sister. It has a the MIL on with codes P0171 and P0174 and has a hunting on start up and will go away after about three to five minutes. I have checked for vacuum leaks and fond none. I pulled the Mass Air Fl...
October 09, 2007
1997 Ford Ranger XLT 4.0L MIL Lamp on VIN: 1FTCR11X6V
P0171: system lean. Hello Group, This Ranger has these 2 codes stored. We have checked the usual suspects (MAF,Intake seal leaks,O2 sensors etc.) with no problem found. The O2 sensors are stuck on 0.0v and fuel trim is -100%. If I force the sensors with propane they still do not ...
October 12, 2007
2000 Ford Explorer XLT 4.0L MIL Lamp on VIN: 1FMZU73X2Y
P0171: Bank 1 system lean. AT IDLE bank2 long trim +10% bank1 LT -6 short trim 0% ST -2 AT 2500 RPM bank2 LT+11 BANK1 LT+11 SH 0 ST -8
October 13, 2007
2004 Audi A8 Quattro L 4.2L MIL Lamp on VIN: WAUML44E94
P0171: lean bank 1. Thanks for taking time to read this. Help all audi techs. This A8 came in for a regular oil change a couple days ago. Came back with above listed codes. Found hose for air pump disconnected from air box. reconnected hose cleared codes and sent it on its way. N...
October 15, 2007
2002 Ford Focus ZTW 2.0L MIL Lamp on, Fuel trim VIN: 1FAHP36392
P0171: Lean Bank 1. This Focus is a well maintained (by me)vehicle. Check engine light came on, lean bank one. Performed a tune up checked for vaccum leaks (no smoke machine) and found a pipe to the very lower back of the intake possibly leaking. I sealed that up and drove the ve...
October 15, 2007
1997 Jeep Grand Cherokee Laredo 4.0L Poor Idle Quality VIN: 1J4GZ58S9V
P0171: Fuel System Lean (Bank 1). ... (OEM) about 3 1/2 months ago the vehicle has come back 3 times with the same problem, engine has an unstable idle, runs rich, loss of power and ck. engine light on (P0171) after replacing the front oxygen sensor (2 after market and 1 OEM) the engine runs n...
October 17, 2007
2000 Chevrolet S10 4.3L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on VIN: 1GCCT19WXY
P0171: Fuel System Lean. 02 sensor stick on lean an bank i runs rich
October 19, 2007
2005 Ford Ranger Edge 3.0L Poor Idle Quality, MIL Lamp on VIN: 1FTYR10U65
P0171: Bank 1 system lean. ... ranger. It has a lean code p0171 and a slightly rough idle. ive smoke tested the intake hot, cold, in between and no leaks. Checked compression and engine vaccum thinking recessed valve seats but everything checks out ok. The MAF seems to be reading proper...
October 23, 2007
2002 GMC Sonoma SL 2.2L Poor Idle Quality, Surge, MIL Lamp on VIN: 1GTCS14582
P0171: Fuel System Lean. ... After firing it up it ran fine for 2 days and then started missing. Found an injector harness plug not fully seated. Good to go. Came back 1 week later with P0171- system too lean bank 1 code set and idle so high that owne...
October 24, 2007
1997 Toyota Camry CE 2.2L MIL Lamp on, Lacks Power VIN: 4T1BG22K5V
P0171: Fuel System Too Lean (Bank 1). ... Engine" light on - code P0171 lean condition. On a test drive it is a total slug under load - won't rev past 3,000 rpm at full throttle. Will get up to speed if you nurse the pedal. Fuel pressure 51 psi and remains good when symptons occur. Adding fue...
October 24, 2007
1999 Saab 9-3 2.0L Poor Fuel Economy, MIL Lamp on VIN: YS3DD58N6X
P0171: long term fuel trim fault. Vehicle presented with cel. Inspection revealed a failing map sensor. Replaced map sensor and cleared codes. Ok on our test drive. Cel came back on a couple of days after customer picked up, same codes. Customer reports gas mileage worse when cel is on. Smoke ...
October 25, 2007
2000 Toyota Tacoma DLX 3.4L MIL Lamp on VIN: 4TAWN72N3Y
P0171: Fuel System Too Lean (Bank 1). ... with code p0171, bank one too lean. another shop has already installed upstream oxygen sensor and fuel filter. fuel pressure is good, i've check for vacuum leaks with carb cleaner, propane, and a smoke machine. coolant temp sensor is reading correctly, o2 ...
October 25, 2007
2001 Lexus GS300 3.0L Hesitation VIN: JT8BD69S91
P0171: Fuel System Too Lean (Bank 1). I can not check fuel press. yet until the special fitting I order comes in,but I will update as soon as I can.This car came in with mil light on and code PO171 lean.Every thing looks good on a scanner except the maf reading is a little off at 2500 rpm's should...
October 29, 2007
1999 Toyota 4Runner Limited 3.4L Poor Idle Quality, Poor Fuel Economy, MIL Lamp on VIN: JT3GN87ROX
P0171: Fuel System Too Lean (Bank 1). This 99 Toyota 4-Runner has a PO171 System lean code, fuel trim is going crazy, smoked the system, no leaks found, fuel pressure is good, no leaks in the air induction system, O2's are good, MAF tests good... Thanks in advance for your assistance. David
October 29, 2007
2001 Mazda Protege ES 2.0L Misfire, MIL Lamp on VIN: JM1BJ22591
P0171: Adaptive Fuel Trim Too Lean (Bank 1). hello all, i am dealing with a 2001 mazda protege that has an intermittent misfire that causes the engine to die or stumble. it has code p300 (random/multiple misfire). both of the coils check out fine.
October 31, 2007