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P0171 Diagnostic Trouble Code Discussion for November 2010

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2002 Chevrolet Silverado 1500 5.3L MIL Lamp on VIN: 2GCEC19T72
P0171: Fuel Trim System Lean (Bank 1). I was second on this jog and found intake leaking with smoke text. Replaced gasket. and fuel trim long turm stays at 25% low at 0% until car worms up . then it starts working normal . I think it needs to be flashed. check light was on for two years. so i think...
November 02, 2010
1997 Ford Mustang SVT Cobra 4.6L Lean idle VIN: 1FALP47V5V
P0171: Lean fuel trim. car came in with p0171 and p0174. found some degraded evap vacuum hoses from the can to the solenoid to the engine. replaced those-not much help. tested fuel system pressure and found it low. replaced fuel pump and pressure is now in spec. however, the lean ...
November 03, 2010
1994 Saab 900 S 2.3L 3000 rpm idle VIN: YS30M55B3R
P0171: Fuel Trim Max value lean. Vehicle VERY intermittantly idles at 3000+ rpm. RPM climbs in stages 1200, 1800, etc... All electrical test good on static system. No tests have been performed during failure. Have only verified once. Has been verified by manager twice. During verified failure...
November 03, 2010
2003 Ford F-150 King Ranch 4.6L Surge, MIL Lamp on VIN: 1FTRW07603
P0171: system lean bank 1. cel light on,when idling,truck is loading up likes its to rich,but i,m getting lean codes,all o2,s indicating lean and reading .05v,heater o2 1000ma,heater o2s indicating on,ect- 191,cyl head temp- 392,loop status- open,maf- 6.2,maf volts-.92,fuel pulse width ...
November 04, 2010
2005 Cadillac STS 4.6L MIL Lamp on VIN: 1G6DC67A75
P0171: Fuel Trim System Lean (Bank 1). need help i cant find whats keeping my fuel trim up mostly on bank 2 at idle its around +15 bank 1 +9 at idle tryed massair flow smoked intake put intake gaskets in fuel trims climb on highway on decel also cleaned injectors found vaccum hose on back of intake...
November 05, 2010
2001 Ford F-150 XLT 5.4L Poor Idle Quality, MIL Lamp on VIN: 1FTRW08L71
P0171: Bank 1 lean condition. ... came to the shop to shop with check engine light on, codes p0171 p0174 we smoke engine found couple of vacuum leaks (egr idle control valve vacuum hose) so we replace this parts, but, the surpreise is that, still running...
November 09, 2010
2004 Ford F-150 Lariat 5.4L Poor Idle Quality, Surge, Cuts out, Stall, Misfire, Poor Fuel Economy, MIL Lamp on
P0171: lean. had lean codes after much hair pulling i found vacuum leak to be problem
November 12, 2010
2003 Ford Expedition XLT 4.6L Poor Idle Quality VIN: 1FMRU15W13
P0171: Bank 1. The engine runs good cold as it warms up and gets to closed loop operation the engine starts runing rough at idle runs good driving.fuel trims were in the minus 4 short term long term -21 pinched off the purge valve at idle it made a differance in the idle and...
November 16, 2010
2001 Ford Explorer XLT 4.0L MIL Lamp on VIN: IFMZU73E91
P0171: Bank 1 Lean. Had this vehicle in for the 2 codes listed about 2 weeks ago After going over the basics, i thought about the intake gaskets, I had fuel trims of LT +25 and ST+20 on both banks when cold at high speed they went slightly lower about +10. After exhausting everyt...
November 17, 2010
1999 Ford Ranger XLT 4.0L Excessive Emissions, Poor Idle Quality, MIL Lamp on VIN: 1FTZR15XOX
P0171: lean condition bank 1. ... would appreciate your assistence. We have here a 99 Ford Ranger 4wd pick up with a 4.0l v6 and automatic transmision. The truck has 192k miles and the second motor 100k miles. After installing a set of new casting cylinder heads the truck returned with bot...
November 18, 2010
1999 Ford Ranger XLT 4.0L Excessive Emissions, Poor Idle Quality, MIL Lamp on VIN: 1FTZR15XOX
P0171: lean condition bank 1. ... would appreciate your assistence. We have here a 99 Ford Ranger 4wd pick up with a 4.0l v6 and automatic transmision. The truck has 192k miles and the second motor 100k miles. After installing a set of new casting cylinder heads the truck returned with bot...
November 23, 2010
2000 Ford Explorer XLT 4.0L Poor Idle Quality VIN: 1FMZU75E0Y
P0171: bank one system lean. have resealed intakes twice, fuel pressure good, have smoke tested engine using the power brake booster hose. Smoke coming out of IAC hose on middle of intake and crankcase ventilation hose on right side valve cover..question: is this normal? what am I missing...
November 28, 2010
1999 Ford F-150 5.4L Poor Idle Quality, Surge, Stall VIN: 1FTRF17Z5X
P0171: system too lean. ... sensor for a P0171 lean code he had. He said he replaced the mass airflow sensor and relized it made no real difference and brought it to me. There is no codes pending or present at this time and the engine is idling rough...
November 29, 2010
2004 Jeep Grand Cherokee Laredo 4.0L Excessive Emissions, Poor Idle Quality, Stall, MIL Lamp on VIN: 1J4GW48SX4
P0171: Fuel System Lean (Bank 1). ... low idle and stalls at stop cold. It would idle rough on first start in morning but would clear up after it started to warm up a few minutes. I also now have a code p1686 for "no sentry key immobilizer bus message" and at time the vehicle will star...
November 29, 2010
2002 Chevrolet Silverado 1500 5.3L MIL Lamp on VIN: 2GCEC19T72
P0171: Fuel Trim System Lean (Bank 1). I was second on this jog and found intake leaking with smoke text. Replaced gasket. and fuel trim long turm stays at 25% low at 0% until car worms up . then it starts working normal . I think it needs to be flashed. check light was on for two years. so i think...
November 02, 2010
1997 Ford Mustang SVT Cobra 4.6L Lean idle VIN: 1FALP47V5V
P0171: Lean fuel trim. car came in with p0171 and p0174. found some degraded evap vacuum hoses from the can to the solenoid to the engine. replaced those-not much help. tested fuel system pressure and found it low. replaced fuel pump and pressure is now in spec. however, the lean ...
November 03, 2010
1994 Saab 900 S 2.3L 3000 rpm idle VIN: YS30M55B3R
P0171: Fuel Trim Max value lean. Vehicle VERY intermittantly idles at 3000+ rpm. RPM climbs in stages 1200, 1800, etc... All electrical test good on static system. No tests have been performed during failure. Have only verified once. Has been verified by manager twice. During verified failure...
November 03, 2010
2003 Ford F-150 King Ranch 4.6L Surge, MIL Lamp on VIN: 1FTRW07603
P0171: system lean bank 1. cel light on,when idling,truck is loading up likes its to rich,but i,m getting lean codes,all o2,s indicating lean and reading .05v,heater o2 1000ma,heater o2s indicating on,ect- 191,cyl head temp- 392,loop status- open,maf- 6.2,maf volts-.92,fuel pulse width ...
November 04, 2010
2005 Cadillac STS 4.6L MIL Lamp on VIN: 1G6DC67A75
P0171: Fuel Trim System Lean (Bank 1). need help i cant find whats keeping my fuel trim up mostly on bank 2 at idle its around +15 bank 1 +9 at idle tryed massair flow smoked intake put intake gaskets in fuel trims climb on highway on decel also cleaned injectors found vaccum hose on back of intake...
November 05, 2010
2001 Ford F-150 XLT 5.4L Poor Idle Quality, MIL Lamp on VIN: 1FTRW08L71
P0171: Bank 1 lean condition. ... came to the shop to shop with check engine light on, codes p0171 p0174 we smoke engine found couple of vacuum leaks (egr idle control valve vacuum hose) so we replace this parts, but, the surpreise is that, still running...
November 09, 2010
2004 Ford F-150 Lariat 5.4L Poor Idle Quality, Surge, Cuts out, Stall, Misfire, Poor Fuel Economy, MIL Lamp on
P0171: lean. had lean codes after much hair pulling i found vacuum leak to be problem
November 12, 2010
2003 Ford Expedition XLT 4.6L Poor Idle Quality VIN: 1FMRU15W13
P0171: Bank 1. The engine runs good cold as it warms up and gets to closed loop operation the engine starts runing rough at idle runs good driving.fuel trims were in the minus 4 short term long term -21 pinched off the purge valve at idle it made a differance in the idle and...
November 16, 2010
2001 Ford Explorer XLT 4.0L MIL Lamp on VIN: IFMZU73E91
P0171: Bank 1 Lean. Had this vehicle in for the 2 codes listed about 2 weeks ago After going over the basics, i thought about the intake gaskets, I had fuel trims of LT +25 and ST+20 on both banks when cold at high speed they went slightly lower about +10. After exhausting everyt...
November 17, 2010
1999 Ford Ranger XLT 4.0L Excessive Emissions, Poor Idle Quality, MIL Lamp on VIN: 1FTZR15XOX
P0171: lean condition bank 1. ... would appreciate your assistence. We have here a 99 Ford Ranger 4wd pick up with a 4.0l v6 and automatic transmision. The truck has 192k miles and the second motor 100k miles. After installing a set of new casting cylinder heads the truck returned with bot...
November 18, 2010
1999 Ford Ranger XLT 4.0L Excessive Emissions, Poor Idle Quality, MIL Lamp on VIN: 1FTZR15XOX
P0171: lean condition bank 1. ... would appreciate your assistence. We have here a 99 Ford Ranger 4wd pick up with a 4.0l v6 and automatic transmision. The truck has 192k miles and the second motor 100k miles. After installing a set of new casting cylinder heads the truck returned with bot...
November 23, 2010
2000 Ford Explorer XLT 4.0L Poor Idle Quality VIN: 1FMZU75E0Y
P0171: bank one system lean. have resealed intakes twice, fuel pressure good, have smoke tested engine using the power brake booster hose. Smoke coming out of IAC hose on middle of intake and crankcase ventilation hose on right side valve cover..question: is this normal? what am I missing...
November 28, 2010
1999 Ford F-150 5.4L Poor Idle Quality, Surge, Stall VIN: 1FTRF17Z5X
P0171: system too lean. ... sensor for a P0171 lean code he had. He said he replaced the mass airflow sensor and relized it made no real difference and brought it to me. There is no codes pending or present at this time and the engine is idling rough...
November 29, 2010
2004 Jeep Grand Cherokee Laredo 4.0L Excessive Emissions, Poor Idle Quality, Stall, MIL Lamp on VIN: 1J4GW48SX4
P0171: Fuel System Lean (Bank 1). ... low idle and stalls at stop cold. It would idle rough on first start in morning but would clear up after it started to warm up a few minutes. I also now have a code p1686 for "no sentry key immobilizer bus message" and at time the vehicle will star...
November 29, 2010