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P0171 Diagnostic Trouble Code Discussion for August 2012

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2001 BMW 740i 4.4L MIL Lamp on VIN: WBAGG834X1
P0171: System too lean bank 1. I have smoked the system and found 2 leaks one from the breather valve that has the brake booster hose on it and the o-ring for the cam shaft sensor. I replaced both and both long term fuel trims go up past 20. I smoke tested after replacing the valve and the ...
August 21, 2012
2000 Chevrolet Prizm 1.8L Hesitation VIN: 1Y1SK5487Y
P0171: Lean condition. last effort have been working with Identfix too, started out BAD flat spot taking off from light, that sysmptom better after all the above parts replaced BUT still has a lagg when at constant speed & try to accelerate if you slowely come off accelerator pe...
August 25, 2012
2000 Cadillac Escalade 5.7L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 1GYEK63R9Y
P0171: Fuel Trim System Lean (Bank 1). This GM truck idles poor and will hesitate on acceleration. Dealer told her the fuel injectors are leaking. Fuel pressure is 57 PSI engine running or not. Pressure will dead head at 75 PSI and engine will idle smooth. Spec is 60-66 PSI, so we know it is low on...
August 27, 2012
2000 Cadillac Escalade 5.7L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 1GYEK63R9Y
P0171: Fuel Trim System Lean (Bank 1). This GM truck idles poor and will hesitate on acceleration. Dealer told her the fuel injectors are leaking. Fuel pressure is 57 PSI engine running or not. Pressure will dead head at 75 PSI and engine will idle smooth. Spec is 60-66 PSI, so we know it is low on...
August 28, 2012
2006 Jeep Commander (Truck) 3.7L MIL Lamp on VIN: 1J8HG48K46
P0171: Bank 1 lean. ... This Jeep came in with both of the codes listed above 2 weeks ago. Basically long story short we found out alot previous repair history on this vehicle that the customer did not up front tell us of course.. It's throwing p0171 and p0174 codes- fuel trims a...
August 28, 2012
2002 Subaru Legacy L 2.5L Poor Idle Quality, Surge, Stall, MIL Lamp on VIN: 4S3BH63502
P0171: Fuel System Too Lean (Bank 1). ... Reflashed computer p0065 gone but still have surging idle and stalling, also now getting p0171. P0065 is gone. Replaced A/F sensor no change, st ft is at 37.5% lt ft 0. Checked fuel no water and clean good fuel pressure and volu...
August 28, 2012
2005 Chevrolet Silverado 1500 LS 5.3L Excessive Emissions, Poor Idle Quality, Surge, Misfire, Poor Fuel Economy, MIL Lamp on VIN: 2GCEK13T25
P0171: Fuel Trim System Lean (Bank 1). The customer was on a road trip and the transmission went out. So he had a reman trans installed, when he got the truck back the check engine light was on. He said that the had never been on, he told the guy at the shop he "scanned" it and they told hi...
August 29, 2012
2004 Mazda MPV ES 3.0L MIL Lamp on
P0171: Adaptive Fuel Trim Too Lean (Bank 1). I replaced bank 2 oxygen sensor. That was the first code it came in with. Since then after a few days, it came bank with a bank 1 and 2 lean. Both primary oxygen senors show very lean at idle, as soon as you raise the idle,they begin to respond more normally. ...
August 29, 2012
2001 Mercury Sable LS Premium 3.0L MIL Lamp on VIN: 1MEFM55S51
P0171: System lean Bank 1. This one came to us with these lovely codes that no one else could fix and apparently not me either. I usually have pretty good luck with these on a Ford. Anyway the only problem is the lights, the car runs fine. Idle may be a bit on the high side cold (1400 a...
August 29, 2012
2006 Jeep Commander (Truck) 3.7L MIL Lamp on VIN: 1J8HG48K46
P0171: Bank 1 lean. ... This Jeep came in with both of the codes listed above 2 weeks ago. Basically long story short we found out alot previous repair history on this vehicle that the customer did not up front tell us of course.. It's throwing p0171 and p0174 codes- fuel trims a...
August 30, 2012
1998 Lexus ES300 3.0L MIL Lamp on VIN: JT8BF28G8W
P0171: Fuel System Too Lean (Bank 1). the vehicle came in with a #p0171 code, I have over time replaced the air flow meter & all of the o2 sensors using factory parts, I have smoked the intake system & there are no leaks. I will clear the codes & run the vehicle at the shop & there...
August 30, 2012
2001 BMW 740i 4.4L MIL Lamp on VIN: WBAGG834X1
P0171: System too lean bank 1. I have smoked the system and found 2 leaks one from the breather valve that has the brake booster hose on it and the o-ring for the cam shaft sensor. I replaced both and both long term fuel trims go up past 20. I smoke tested after replacing the valve and the ...
August 21, 2012
2000 Chevrolet Prizm 1.8L Hesitation VIN: 1Y1SK5487Y
P0171: Lean condition. last effort have been working with Identfix too, started out BAD flat spot taking off from light, that sysmptom better after all the above parts replaced BUT still has a lagg when at constant speed & try to accelerate if you slowely come off accelerator pe...
August 25, 2012
2000 Cadillac Escalade 5.7L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 1GYEK63R9Y
P0171: Fuel Trim System Lean (Bank 1). This GM truck idles poor and will hesitate on acceleration. Dealer told her the fuel injectors are leaking. Fuel pressure is 57 PSI engine running or not. Pressure will dead head at 75 PSI and engine will idle smooth. Spec is 60-66 PSI, so we know it is low on...
August 27, 2012
2000 Cadillac Escalade 5.7L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 1GYEK63R9Y
P0171: Fuel Trim System Lean (Bank 1). This GM truck idles poor and will hesitate on acceleration. Dealer told her the fuel injectors are leaking. Fuel pressure is 57 PSI engine running or not. Pressure will dead head at 75 PSI and engine will idle smooth. Spec is 60-66 PSI, so we know it is low on...
August 28, 2012
2006 Jeep Commander (Truck) 3.7L MIL Lamp on VIN: 1J8HG48K46
P0171: Bank 1 lean. ... codes listed above 2 weeks ago. Basically long story short we found out alot previous repair history on this vehicle that the customer did not up front tell us of course.. It's throwing p0171 and p0174 codes- fuel trims a...
August 28, 2012
2002 Subaru Legacy L 2.5L Poor Idle Quality, Surge, Stall, MIL Lamp on VIN: 4S3BH63502
P0171: Fuel System Too Lean (Bank 1). ... Reflashed computer p0065 gone but still have surging idle and stalling, also now getting p0171. P0065 is gone. Replaced A/F sensor no change, st ft is at 37.5% lt ft 0. Checked fuel no water and clean good fuel pressure and volu...
August 28, 2012
2005 Chevrolet Silverado 1500 LS 5.3L Excessive Emissions, Poor Idle Quality, Surge, Misfire, Poor Fuel Economy, MIL Lamp on VIN: 2GCEK13T25
P0171: Fuel Trim System Lean (Bank 1). The customer was on a road trip and the transmission went out. So he had a reman trans installed, when he got the truck back the check engine light was on. He said that the had never been on, he told the guy at the shop he "scanned" it and they told hi...
August 29, 2012
2004 Mazda MPV ES 3.0L MIL Lamp on
P0171: Adaptive Fuel Trim Too Lean (Bank 1). I replaced bank 2 oxygen sensor. That was the first code it came in with. Since then after a few days, it came bank with a bank 1 and 2 lean. Both primary oxygen senors show very lean at idle, as soon as you raise the idle,they begin to respond more normally. ...
August 29, 2012
2001 Mercury Sable LS Premium 3.0L MIL Lamp on VIN: 1MEFM55S51
P0171: System lean Bank 1. This one came to us with these lovely codes that no one else could fix and apparently not me either. I usually have pretty good luck with these on a Ford. Anyway the only problem is the lights, the car runs fine. Idle may be a bit on the high side cold (1400 a...
August 29, 2012
2006 Jeep Commander (Truck) 3.7L MIL Lamp on VIN: 1J8HG48K46
P0171: Bank 1 lean. ... codes listed above 2 weeks ago. Basically long story short we found out alot previous repair history on this vehicle that the customer did not up front tell us of course.. It's throwing p0171 and p0174 codes- fuel trims a...
August 30, 2012
1998 Lexus ES300 3.0L MIL Lamp on VIN: JT8BF28G8W
P0171: Fuel System Too Lean (Bank 1). the vehicle came in with a #p0171 code, I have over time replaced the air flow meter & all of the o2 sensors using factory parts, I have smoked the intake system & there are no leaks. I will clear the codes & run the vehicle at the shop & there...
August 30, 2012