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P0171 Diagnostic Trouble Code Discussion for February 2009

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2005 Chevrolet Malibu 2.2L MIL Lamp on VIN: 1G1ZS54F15
P0171: Fuel System Lean (Bank 1). high fuel trims at extended idle vehicle came in for service had a check engine light on indicating bank one running lean. sprayed carb cleaner over whole engine area and found no change in fuel trims. long term fuel trims are fine while driving but creep back...
February 03, 2009
2000 Nissan Sentra XE 1.8L MIL Lamp on
P0171: Fuel Trim Lean. this car has a p0171 code , i scoped the both front 02s, b1 looks good, switches properly , reacts quickly, and peaks over 800mv and below 200mv.bank 2 sensor 1 was a little slow to react, but not horrible.i've seen alot of 02 sensor traces in my time and this...
February 03, 2009
2000 Ford Taurus SE 2-Valve 3.0L Poor Idle Quality, Hesitation, Surge, Poor Fuel Economy, MIL Lamp on VIN: 1FAFP5525Y
P0171: lean. Hi guys thanks for your repsonses in advance. I have a lean condition with this taurus. long term trim is at 33%+ and short term 22% both banks. car seems to run better until it hits closed loop. then when computer takes over. smoke tested for vacume leans as ...
February 04, 2009
2000 Ford F-150 Lariat 5.4L Stall, Misfire VIN: 1FTRX18L6Y
P0171: Bank 1 Lean. This truck was sent to us from another shop. The complaint is rough idle & acts like going to stall occas. at stops. Codes 171,174 were present. We "smoke" tested the engine & found no leaks, other than a collapsed pcv hose, which we replaced. ...
February 04, 2009
2000 Nissan Sentra XE 1.8L MIL Lamp on
P0171: Fuel Trim Lean. this car has a p0171 code , i scoped the both front 02s, b1 looks good, switches properly , reacts quickly, and peaks over 800mv and below 200mv.bank 2 sensor 1 was a little slow to react, but not horrible.i've seen alot of 02 sensor traces in my time and this...
February 04, 2009
2002 Chevrolet Silverado 1500 5.3L Poor Idle Quality, Surge, Misfire, MIL Lamp on VIN: IGCEK19T22
P0171: Fuel Trim System Lean (Bank 1). Hi Gang! This is my brothers truck, has had an on going problem with this vehicle. Only when cold there is a noticeable misfire and rough running with the MIL coming on and reading the above codes. I have performed basic system checks but found nothing outn of...
February 05, 2009
1999 Ford Ranger XL 3.0L Poor Idle Quality, Hesitation, Cuts out VIN: 1FTYR10V3X
P0171: lean bank one. ... no power on take off feels like running out of gas. Check for codes had P0171,174,1131,1151, short term fuel trim running between 28 and 34 both banks, and long term in the 20's both banks,both upstream 02's are between ...
February 05, 2009
2000 Ford F-150 Lariat 5.4L Stall, Misfire VIN: 1FTRX18L6Y
P0171: Bank 1 Lean. This truck was sent to us from another shop. The complaint is rough idle & acts like going to stall occas. at stops. Codes 171,174 were present. We "smoke" tested the engine & found no leaks, other than a collapsed pcv hose, which we replaced. ...
February 05, 2009
2003 Ford F-250 Super Duty XL 5.4L MIL Lamp on VIN: 1FTNF21L93
P0171: Lean Bank 1. This truck has been a thorn in my side.came in a month ago with codes PO171 & PO174.I checked for vaccumn Leaks. None found.Replaced Mass air flow meter & PCV Valve.Sent him on his way.Two days later back with same codes.Double checked for vac leaks(ba...
February 05, 2009
2001 Mazda MPV DX 2.5L monitors VIN: JM3LW28G61
P0171: Adaptive Fuel Trim Too Lean (Bank 1). the vehicle had failed emmission for the mil being on for code po171, po174, po306, po303. We smoke tested the engine to find that the pcv hose was leaking and also the lower intake gaskets. After repair was done, we drove the drive cycle and 3 monitors had no...
February 05, 2009
2001 Toyota Sienna LE 3.0L MIL Lamp on VIN: 4TS2F13C91
P0171: Fuel System Too Lean (Bank 1). ... about 3 months ago requesting a 60K mile service. It was about 8,000 miles early, but we were happy to perform this early service, 3 months roll by and 100+ cars later, theyre back with a check engine light, we cleared the code which was for the inactive o...
February 06, 2009
1999 Ford F-150 4.2L Poor Idle Quality, Stall, MIL Lamp on VIN: 1FTZS1725X
P0171: lean exhaust. ... the students has a 1999 F 150 4.2l, auto.That has the follwing codes P0171 and P0174 lean exhaust on both banks and a unstable idle after a hot soak restart. We have not been able to see anything wrong on the scan data ...
February 08, 2009
1999 Ford Windstar SEL 3.8L MIL Lamp on VIN: 2FMDA5348X
P0171: lean bank 1. This car has come back to me twice now. Originally it had lean codes on bank 1 and bank 2. Atleast once a week Im given a Ford with 171/174. I bring it in, smoke it, slap a MAF on it (only if it has both codes) and its fixed. Same happened here, but it came ba...
February 09, 2009
2003 GMC Yukon Denali 6.0L Poor Idle Quality, Surge, MIL Lamp on VIN: 1GKEK63UX3
P0171: Fuel Trim System Lean (Bank 1). ... (MAF Sensor), P0171 and P0174 (right and left bank too lean). Previous repair history: MAF sensor checks out ok, throttle body was cleaned, PCV was replaced, and fuel filter was replaced. After performing work the light stayed out for a few days and then...
February 09, 2009
2004 Ford F-150 STX 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FTRX12W64
P0171: system lean bank 1. We got 2004 f-150 with 4.6l engine came in with bad miss fire and MIL on.check the code memory has p171,p300,p354 and p304,p305,p307.Check vacum leak not detected.check exhust system no restriction.fuel pressure 41 psi at idle and 41-42 at high rpm.BAnk to o2 ...
February 11, 2009
2002 Toyota Corolla CE 1.8L No Start VIN: 1NXBR12E22
P0171: Fuel System Too Lean (Bank 1). ... sure if p0171 is related to this problem. did find a small vac leak at intake gasket.has any one seen this befor.or any good ways to check the evap system on this car.Mitchell is not giving me what i'm looking for.
February 11, 2009
1999 Chevrolet K1500 Suburban 5.7L Poor Idle Quality, Hesitation, Surge, Cuts out, MIL Lamp on VIN: 1GKFK16R1X
P0171: Fuel Trim System Lean (Bank 1). ... to read and respond to this one. This Surburban is giving me a major headache! Customer tuned it up himself and replaced the listed parts. Came to me running rough, checked cap and rotor and found rotor loose, fixed that and replaced the cap. Reset cam sy...
February 12, 2009
2007 Chevrolet HHR LS 2.2L MIL Lamp on VIN: 3GNDA13D47
P0171: Fuel System Lean. ... emissions test, found p0171, smoke tested and found no vacuum leaks, car runs like a champ, STFT changes between -3 to 5 %, but LTFT is almost always pegged to 30%. Found a TSB that says to replace injectors with a different part number and reflash the ec...
February 12, 2009
2005 Honda Accord EX 3.0L MIL Lamp on VIN: 1HGCM81654
P0171: Fuel System Too Lean (Bank 1). ... came back with ses light codes p0171 and p0174. checked for vacuum leaks. smoke tested none found. fuel pressure good 57 psi. made sure ethanol was not used in vehicle fuel alcohol content at 4%. followed alldata diagnostics which led to valve adjustment w...
February 13, 2009
1999 Ford Ranger XLT 4.0L Poor Fuel Economy, MIL Lamp on VIN: 1FTYR11X5X
P0171: lean rich limit bank 1. CHECK ENGINE LIGHT COMES ON AFTER ABOUT 2 WEEKS WITH THE SAME CODES ALL THE TIME. WE HAVE CHANGED 1 OF THE O2 AND HAVE CHECKED FOR VAC LEAKS AND HAVE CLEANED THE MASS AIR FLOW AS INSTRUCTED IN THE TSB 98-06-08. all is fine for about 2 or more weeks and then th...
February 17, 2009
1999 Ford Expedition XLT 4.6L Poor Idle Quality, MIL Lamp on VIN: 1FMRU1868X
P0171: lean bank 1. Hello all. This vehicle came in with a cel on and misfire code. Foiund failed plug wires. Replaced plugs wires fuel and air filter. Test drove runs fine. Returned vehicle to customer. 500 miles later vehicle comes in with po171 po 174 code. Check maf sensor wa...
February 19, 2009
2000 Honda Accord EX 3.0L MIL Lamp on VIN: 1HGCG1654Y
P0171: Fuel System Too Lean (Bank 1). ... and code p0171 set. Fuel trims near zero while cruising - long term fuel trim creeps up to 13 or 14 at extended idle. It seemed to have a vacuum leak at the egr valve. We replaced the valve and nothing changed. We blocked off the egr valve with a solid gas...
February 20, 2009
1997 Ford Ranger XL 4.0L MIL Lamp on VIN: 1FTCR14X8U
P0171: system too lean bank 1. Hello Everyone, need help.Check engine light on 1 month ago. Came in with codes PO171 & PO174 RUNS GREAT NO COMPLANTS EXCEPT CHECK ENGINE LIGHT ON.. Test drove with codes cleared for 20 miles the codes have no reset so for. I am showing LONG TERM FUEL TRIM...
February 22, 2009
1999 Chevrolet K1500 Suburban 5.7L Poor Idle Quality, Hesitation, Surge, Cuts out, MIL Lamp on VIN: 1GKFK16R1X
P0171: Fuel Trim System Lean (Bank 1). ... to read and respond to this one. This Surburban is giving me a major headache! Customer tuned it up himself and replaced the listed parts. Came to me running rough, checked cap and rotor and found rotor loose, fixed that and replaced the cap. Reset cam sy...
February 23, 2009
2000 Acura TL 3.2L Misfire, MIL Lamp on VIN: 19UUA5666Y
P0171: Fuel System Too Lean (Bank 1). Hello everyone. We have a Acura 3.2TL that came in with a flashing MIL light and a misfire on almost every cylinder. We removed the intake manifolds and cleaned the clogged EGR ports but the misfire is still present. We checked compression- good. We can not ho...
February 24, 2009
1998 Toyota RAV4 2.0L Excessive Emissions, Poor Fuel Economy VIN: JT3HP10V1W
P0171: Fuel System Too Lean (Bank 1). ... out there...this rav4 has a p0171 lean code returning daily only 1 time did i see the p0420 the customer has had this to the dealer and they cant figure it out map sensor , o2 sensor have both been replaced fuel pressure has been checked intake smoked, wha...
February 24, 2009
2000 Toyota Corolla VE 1.8L MIL Lamp on VIN: 2T1BR12E0Y
P0171: Fuel System Too Lean (Bank 1). This vehicle was in a front end collision with a deer. The radiator and cooling fan were shoved back and cracked the intake manifold. Upon removal of intake we found antifreeze on the intake valves that were closed. We surmised the only way for the coolant to ...
February 26, 2009
2005 Chevrolet Malibu 2.2L MIL Lamp on VIN: 1G1ZS54F15
P0171: Fuel System Lean (Bank 1). high fuel trims at extended idle vehicle came in for service had a check engine light on indicating bank one running lean. sprayed carb cleaner over whole engine area and found no change in fuel trims. long term fuel trims are fine while driving but creep back...
February 03, 2009
2000 Nissan Sentra XE 1.8L MIL Lamp on
P0171: Fuel Trim Lean. this car has a p0171 code , i scoped the both front 02s, b1 looks good, switches properly , reacts quickly, and peaks over 800mv and below 200mv.bank 2 sensor 1 was a little slow to react, but not horrible.i've seen alot of 02 sensor traces in my time and this...
February 03, 2009
2000 Ford Taurus SE 2-Valve 3.0L Poor Idle Quality, Hesitation, Surge, Poor Fuel Economy, MIL Lamp on VIN: 1FAFP5525Y
P0171: lean. Hi guys thanks for your repsonses in advance. I have a lean condition with this taurus. long term trim is at 33%+ and short term 22% both banks. car seems to run better until it hits closed loop. then when computer takes over. smoke tested for vacume leans as ...
February 04, 2009
2000 Ford F-150 Lariat 5.4L Stall, Misfire VIN: 1FTRX18L6Y
P0171: Bank 1 Lean. This truck was sent to us from another shop. The complaint is rough idle & acts like going to stall occas. at stops. Codes 171,174 were present. We "smoke" tested the engine & found no leaks, other than a collapsed pcv hose, which we replaced. ...
February 04, 2009
2000 Nissan Sentra XE 1.8L MIL Lamp on
P0171: Fuel Trim Lean. this car has a p0171 code , i scoped the both front 02s, b1 looks good, switches properly , reacts quickly, and peaks over 800mv and below 200mv.bank 2 sensor 1 was a little slow to react, but not horrible.i've seen alot of 02 sensor traces in my time and this...
February 04, 2009
2002 Chevrolet Silverado 1500 5.3L Poor Idle Quality, Surge, Misfire, MIL Lamp on VIN: IGCEK19T22
P0171: Fuel Trim System Lean (Bank 1). Hi Gang! This is my brothers truck, has had an on going problem with this vehicle. Only when cold there is a noticeable misfire and rough running with the MIL coming on and reading the above codes. I have performed basic system checks but found nothing outn of...
February 05, 2009
1999 Ford Ranger XL 3.0L Poor Idle Quality, Hesitation, Cuts out VIN: 1FTYR10V3X
P0171: lean bank one. ... no power on take off feels like running out of gas. Check for codes had P0171,174,1131,1151, short term fuel trim running between 28 and 34 both banks, and long term in the 20's both banks,both upstream 02's are between ...
February 05, 2009
2000 Ford F-150 Lariat 5.4L Stall, Misfire VIN: 1FTRX18L6Y
P0171: Bank 1 Lean. This truck was sent to us from another shop. The complaint is rough idle & acts like going to stall occas. at stops. Codes 171,174 were present. We "smoke" tested the engine & found no leaks, other than a collapsed pcv hose, which we replaced. ...
February 05, 2009
2003 Ford F-250 Super Duty XL 5.4L MIL Lamp on VIN: 1FTNF21L93
P0171: Lean Bank 1. This truck has been a thorn in my side.came in a month ago with codes PO171 & PO174.I checked for vaccumn Leaks. None found.Replaced Mass air flow meter & PCV Valve.Sent him on his way.Two days later back with same codes.Double checked for vac leaks(ba...
February 05, 2009
2001 Mazda MPV DX 2.5L monitors VIN: JM3LW28G61
P0171: Adaptive Fuel Trim Too Lean (Bank 1). the vehicle had failed emmission for the mil being on for code po171, po174, po306, po303. We smoke tested the engine to find that the pcv hose was leaking and also the lower intake gaskets. After repair was done, we drove the drive cycle and 3 monitors had no...
February 05, 2009
2001 Toyota Sienna LE 3.0L MIL Lamp on VIN: 4TS2F13C91
P0171: Fuel System Too Lean (Bank 1). ... about 3 months ago requesting a 60K mile service. It was about 8,000 miles early, but we were happy to perform this early service, 3 months roll by and 100+ cars later, theyre back with a check engine light, we cleared the code which was for the inactive o...
February 06, 2009
1999 Ford F-150 4.2L Poor Idle Quality, Stall, MIL Lamp on VIN: 1FTZS1725X
P0171: lean exhaust. ... the students has a 1999 F 150 4.2l, auto.That has the follwing codes P0171 and P0174 lean exhaust on both banks and a unstable idle after a hot soak restart. We have not been able to see anything wrong on the scan data ...
February 08, 2009
1999 Ford Windstar SEL 3.8L MIL Lamp on VIN: 2FMDA5348X
P0171: lean bank 1. This car has come back to me twice now. Originally it had lean codes on bank 1 and bank 2. Atleast once a week Im given a Ford with 171/174. I bring it in, smoke it, slap a MAF on it (only if it has both codes) and its fixed. Same happened here, but it came ba...
February 09, 2009
2003 GMC Yukon Denali 6.0L Poor Idle Quality, Surge, MIL Lamp on VIN: 1GKEK63UX3
P0171: Fuel Trim System Lean (Bank 1). ... (MAF Sensor), P0171 and P0174 (right and left bank too lean). Previous repair history: MAF sensor checks out ok, throttle body was cleaned, PCV was replaced, and fuel filter was replaced. After performing work the light stayed out for a few days and then...
February 09, 2009
2004 Ford F-150 STX 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FTRX12W64
P0171: system lean bank 1. We got 2004 f-150 with 4.6l engine came in with bad miss fire and MIL on.check the code memory has p171,p300,p354 and p304,p305,p307.Check vacum leak not detected.check exhust system no restriction.fuel pressure 41 psi at idle and 41-42 at high rpm.BAnk to o2 ...
February 11, 2009
2002 Toyota Corolla CE 1.8L No Start VIN: 1NXBR12E22
P0171: Fuel System Too Lean (Bank 1). ... sure if p0171 is related to this problem. did find a small vac leak at intake gasket.has any one seen this befor.or any good ways to check the evap system on this car.Mitchell is not giving me what i'm looking for.
February 11, 2009
1999 Chevrolet K1500 Suburban 5.7L Poor Idle Quality, Hesitation, Surge, Cuts out, MIL Lamp on VIN: 1GKFK16R1X
P0171: Fuel Trim System Lean (Bank 1). ... to read and respond to this one. This Surburban is giving me a major headache! Customer tuned it up himself and replaced the listed parts. Came to me running rough, checked cap and rotor and found rotor loose, fixed that and replaced the cap. Reset cam sy...
February 12, 2009
2007 Chevrolet HHR LS 2.2L MIL Lamp on VIN: 3GNDA13D47
P0171: Fuel System Lean. ... emissions test, found p0171, smoke tested and found no vacuum leaks, car runs like a champ, STFT changes between -3 to 5 %, but LTFT is almost always pegged to 30%. Found a TSB that says to replace injectors with a different part number and reflash the ec...
February 12, 2009
2005 Honda Accord EX 3.0L MIL Lamp on VIN: 1HGCM81654
P0171: Fuel System Too Lean (Bank 1). ... came back with ses light codes p0171 and p0174. checked for vacuum leaks. smoke tested none found. fuel pressure good 57 psi. made sure ethanol was not used in vehicle fuel alcohol content at 4%. followed alldata diagnostics which led to valve adjustment w...
February 13, 2009
1999 Ford Ranger XLT 4.0L Poor Fuel Economy, MIL Lamp on VIN: 1FTYR11X5X
P0171: lean rich limit bank 1. CHECK ENGINE LIGHT COMES ON AFTER ABOUT 2 WEEKS WITH THE SAME CODES ALL THE TIME. WE HAVE CHANGED 1 OF THE O2 AND HAVE CHECKED FOR VAC LEAKS AND HAVE CLEANED THE MASS AIR FLOW AS INSTRUCTED IN THE TSB 98-06-08. all is fine for about 2 or more weeks and then th...
February 17, 2009
1999 Ford Expedition XLT 4.6L Poor Idle Quality, MIL Lamp on VIN: 1FMRU1868X
P0171: lean bank 1. Hello all. This vehicle came in with a cel on and misfire code. Foiund failed plug wires. Replaced plugs wires fuel and air filter. Test drove runs fine. Returned vehicle to customer. 500 miles later vehicle comes in with po171 po 174 code. Check maf sensor wa...
February 19, 2009
2000 Honda Accord EX 3.0L MIL Lamp on VIN: 1HGCG1654Y
P0171: Fuel System Too Lean (Bank 1). ... and code p0171 set. Fuel trims near zero while cruising - long term fuel trim creeps up to 13 or 14 at extended idle. It seemed to have a vacuum leak at the egr valve. We replaced the valve and nothing changed. We blocked off the egr valve with a solid gas...
February 20, 2009
1997 Ford Ranger XL 4.0L MIL Lamp on VIN: 1FTCR14X8U
P0171: system too lean bank 1. Hello Everyone, need help.Check engine light on 1 month ago. Came in with codes PO171 & PO174 RUNS GREAT NO COMPLANTS EXCEPT CHECK ENGINE LIGHT ON.. Test drove with codes cleared for 20 miles the codes have no reset so for. I am showing LONG TERM FUEL TRIM...
February 22, 2009
1999 Chevrolet K1500 Suburban 5.7L Poor Idle Quality, Hesitation, Surge, Cuts out, MIL Lamp on VIN: 1GKFK16R1X
P0171: Fuel Trim System Lean (Bank 1). ... to read and respond to this one. This Surburban is giving me a major headache! Customer tuned it up himself and replaced the listed parts. Came to me running rough, checked cap and rotor and found rotor loose, fixed that and replaced the cap. Reset cam sy...
February 23, 2009
2000 Acura TL 3.2L Misfire, MIL Lamp on VIN: 19UUA5666Y
P0171: Fuel System Too Lean (Bank 1). Hello everyone. We have a Acura 3.2TL that came in with a flashing MIL light and a misfire on almost every cylinder. We removed the intake manifolds and cleaned the clogged EGR ports but the misfire is still present. We checked compression- good. We can not ho...
February 24, 2009
1998 Toyota RAV4 2.0L Excessive Emissions, Poor Fuel Economy VIN: JT3HP10V1W
P0171: Fuel System Too Lean (Bank 1). ... out there...this rav4 has a p0171 lean code returning daily only 1 time did i see the p0420 the customer has had this to the dealer and they cant figure it out map sensor , o2 sensor have both been replaced fuel pressure has been checked intake smoked, wha...
February 24, 2009
2000 Toyota Corolla VE 1.8L MIL Lamp on VIN: 2T1BR12E0Y
P0171: Fuel System Too Lean (Bank 1). This vehicle was in a front end collision with a deer. The radiator and cooling fan were shoved back and cracked the intake manifold. Upon removal of intake we found antifreeze on the intake valves that were closed. We surmised the only way for the coolant to ...
February 26, 2009