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P0171 Diagnostic Trouble Code Discussion for May 2006

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
1997 Ford Crown Victoria LX 4.6L MIL Lamp on VIN: 2FALP74W4V
P0171: bank 1 system too lean. hey guys...thanx to all in advance...vehicle came for failed emission test due to MIL on...no readings the smog tech just told customer its an automatic fail...customer took vehicle to local Ford dealer where they replaced intake manifold due to coolant leak.....
May 06, 2006
2001 Lexus IS300 3.0L No Start, Poor Idle Quality VIN: JTHBD18251
P0171: Fuel System Too Lean (Bank 1). car came in for intermittent rough idle,mil on,codes p-0171 and p-0174 stored.throttle control motor was making aloud clicking noise w/engine running.unplugged tc motor to scope it, and removed tps sensor to check it.after reassembly ran briefly but w/no throt...
May 07, 2006
2001 Toyota Corolla CE 1.8L MIL Lamp on, power cuts out VIN: 1NXBR12E01
P0171: Fuel System Too Lean (Bank 1). HELP!! Car has code for Bank one lean. I have checked all vacuum hoses, resealed intake and inspected for leaks, replaced the upstream o2 sensor, replaced the fuel injectors(Toyota has a tsb for blockage problems), removed and inspected fuel pump and screen. L...
May 07, 2006
1998 Ford Windstar GL 3.8L MIL Lamp on VIN: 2FMZA5141W
We have a leak around the IMRC shaft on the intake, Ford says they do not service these seals, and requires replacement of intake at 450.00. After searching the archives, and finding all the known problems with the 3.8, I only found one case of the manifold it...
May 08, 2006
2005 Chevrolet Classic 2.2L Poor Idle Quality, Hesitation, Misfire, MIL Lamp on VIN: 1G1ND52F25
P0171: Fuel System Lean. This vehicle runs ok most of the time with no problems. The all of a sudden will begin to run lean and sputter Found A TSB on a faulty fuel pump strainer but fuel pressure is within specifications. No vac leaks found. STFT number range from +20% to +49.2% LTFT...
May 09, 2006
2000 Ford Windstar SEL 3.8L Excessive Emissions, Poor Idle Quality, Stall, Poor Fuel Economy, MIL Lamp on VIN: 2FMZA5345Y
P0171: lean bank 1. HELP!!! I have this Windstar thats driving me crazy.I performed the Ford tsb for the upper intake manifold and gaskets, new l.h. valve cover, changed engine oil and filter, replaced both front o2 sensors. The s.t. and l.t. fuel trims are at minus 20 and both f...
May 09, 2006
2001 Volkswagen Jetta GL 2.0L MIL Lamp on VIN: 3VWRK69M41
P0171: Bank 1 lean. Car came in with P0171 in history woth MIL light on. Have gone through diagnostic flow chart. No Vac leaks fuel pressure good. Any help would be great.
May 10, 2006
2000 Toyota 4Runner SR5 3.4L MIL Lamp on VIN: JT3HN86R0Y
P0171: Fuel System Too Lean (Bank 1). Hello all, need some yota advice. I have a Po171 Fuel Trim Lean with slight power loss but not very noticable. MAF and O2 seem to be doing their job, no obviouse vacuum leaks however the fuel trim is off. Short term is always +/- 5 or so but the longterm chang...
May 11, 2006
1997 Mitsubishi Eclipse RS 2.0L Hesitation, Cuts out, MIL Lamp on VIN: 4A3AK34Y7V
P0171: Fuel System Lean (Bank 1). car came in for a check engine light on and intermitant stalling condition. just sitting here in the shop in park it will idle fine then every few minutes or so it acts like you turned the key off and back on real fast. it starts to stall then comes back and t...
May 13, 2006
1997 Mitsubishi Eclipse RS 2.0L Hesitation, Cuts out, MIL Lamp on VIN: 4A3AK34Y7V
P0171: Fuel System Lean (Bank 1). car came in for a check engine light on and intermitant stalling condition. just sitting here in the shop in park it will idle fine then every few minutes or so it acts like you turned the key off and back on real fast. it starts to stall then comes back and t...
May 15, 2006
1995 Saab 900 S 2.3L MIL Lamp on VIN: YS3DD58B8S
P0171: fuel trim max. value too lean. ... and ect signal. Verified ect O.L., replaced ect and thermostat. Smoke check intake, all O.K. threw P0171 again after t/drive and hot restart. Car claims OBDII compliance but generic scan tools can't communicate and TechII does not support freeze frame data...
May 17, 2006
2001 Ford F-150 XL 4.2L Poor Idle Quality, Cuts out VIN: 2FTZX17211
P0171: System lean bank 1. Fellow Techs, I have this 01 F150 that belongs to my nephew. A little history. He got the truck from his father in Ohio with the heads removed. It had been diagnosted by the dealer as a blown head gasket causing intermittent lean running problems. Was torn dow...
May 20, 2006
2001 Ford F-150 XL 4.2L Poor Idle Quality, Cuts out VIN: 2FTZX17211
P0171: System lean bank 1. Fellow Techs, I have this 01 F150 that belongs to my nephew. A little history. He got the truck from his father in Ohio with the heads removed. It had been diagnosted by the dealer as a blown head gasket causing intermittent lean running problems. Was torn dow...
May 21, 2006
2001 Ford Windstar LX 3.8L code 171 174 VIN: 2FMZA51431
P0171: lean exhaust bank 1. hey ford fans, i have a ton of ford windstars with codes po171 and po174. no vaccum leaks detected O2 seem to be responding well. also have town car with same problem. please help us we are head overheals with ohio e-checks. thank you
May 23, 2006
2001 Infiniti I30 3.0L Hesitation, MIL Lamp on
P0171: Fuel Trim Lean (Bank 1). ... on this one. The code sets in the morning. When I scan the MAF after it is hot, I get a 2.08 reading at 715 rpm in park and a 2.8 reading in drive at 650 rpm. I thought it should be higher at a higher rpm not reversed. Am I right? MAF problem? I know the M...
May 24, 2006
2004 Ford Crown Victoria 4.6L MIL Lamp on VIN: FAFP71W64X
P0171: System too lean Bank 1. Bank one too lean. This sets a code at 1800 rpm and 50 miles of driving. When cheking data stream in shop and driving the short term fuel trim is not lean but on the rich side. Seems like a fuel problem with fuel but cannot find a way to check fuel pressure si...
May 25, 2006
2003 Mitsubishi Montero Limited 3.8L MIL Lamp on VIN: JA4NW51S73
P0171: Fuel System Lean (Bank 1). ... '03 Montero that will set p0171. p0174 codes right away at idle. My fuel trims long and short get fixed at 12.5% long and 25% short term. If I add a small amount of propane, these ramp down to near normal. If I pinch off the fuel return line slightly, the ...
May 30, 2006
2001 Nissan Sentra GXE 1.8L MIL Lamp on VIN: 3N1CB51D21
P0171: Fuel Trim Lean. the car came in with code p0171 checked for exhaust leaks air intake leaks fuel pressure is ok 38 psi and 43 psi with regulator dissconnected maf checks out ok have mitchell info for code followed everything tests ok hopefully im just overlooking something
May 30, 2006
1996 Ford Contour GL 2.0L MIL Lamp on VIN: 1FALP6533T
P0171: system lean bank 1. HI FORD TECHS CAR GETS A PO171 ONLY AFTER DRIVING 72 MPH OR HIGHER. CAR HAS GOOD O2 READINGS GOOD BARO PID GOOD MAF READINGS THE ONLY FREEZE FRAME DATA THAT I DONT KNOW ABOUT IS FULSYS1 OL DRV DOES THIS MEAN FUEL SYSTEM 1 OPEN LOOP IN DRIVE? THE FREEZE FRAME D...
May 31, 2006
1997 Ford Crown Victoria LX 4.6L MIL Lamp on VIN: 2FALP74W4V
P0171: bank 1 system too lean. hey guys...thanx to all in advance...vehicle came for failed emission test due to MIL on...no readings the smog tech just told customer its an automatic fail...customer took vehicle to local Ford dealer where they replaced intake manifold due to coolant leak.....
May 06, 2006
2001 Lexus IS300 3.0L No Start, Poor Idle Quality VIN: JTHBD18251
P0171: Fuel System Too Lean (Bank 1). car came in for intermittent rough idle,mil on,codes p-0171 and p-0174 stored.throttle control motor was making aloud clicking noise w/engine running.unplugged tc motor to scope it, and removed tps sensor to check it.after reassembly ran briefly but w/no throt...
May 07, 2006
2001 Toyota Corolla CE 1.8L MIL Lamp on, power cuts out VIN: 1NXBR12E01
P0171: Fuel System Too Lean (Bank 1). HELP!! Car has code for Bank one lean. I have checked all vacuum hoses, resealed intake and inspected for leaks, replaced the upstream o2 sensor, replaced the fuel injectors(Toyota has a tsb for blockage problems), removed and inspected fuel pump and screen. L...
May 07, 2006
1998 Ford Windstar GL 3.8L MIL Lamp on VIN: 2FMZA5141W
We have a leak around the IMRC shaft on the intake, Ford says they do not service these seals, and requires replacement of intake at 450.00. After searching the archives, and finding all the known problems with the 3.8, I only found one case of the manifold it...
May 08, 2006
2005 Chevrolet Classic 2.2L Poor Idle Quality, Hesitation, Misfire, MIL Lamp on VIN: 1G1ND52F25
P0171: Fuel System Lean. This vehicle runs ok most of the time with no problems. The all of a sudden will begin to run lean and sputter Found A TSB on a faulty fuel pump strainer but fuel pressure is within specifications. No vac leaks found. STFT number range from +20% to +49.2% LTFT...
May 09, 2006
2000 Ford Windstar SEL 3.8L Excessive Emissions, Poor Idle Quality, Stall, Poor Fuel Economy, MIL Lamp on VIN: 2FMZA5345Y
P0171: lean bank 1. HELP!!! I have this Windstar thats driving me crazy.I performed the Ford tsb for the upper intake manifold and gaskets, new l.h. valve cover, changed engine oil and filter, replaced both front o2 sensors. The s.t. and l.t. fuel trims are at minus 20 and both f...
May 09, 2006
2001 Volkswagen Jetta GL 2.0L MIL Lamp on VIN: 3VWRK69M41
P0171: Bank 1 lean. Car came in with P0171 in history woth MIL light on. Have gone through diagnostic flow chart. No Vac leaks fuel pressure good. Any help would be great.
May 10, 2006
2000 Toyota 4Runner SR5 3.4L MIL Lamp on VIN: JT3HN86R0Y
P0171: Fuel System Too Lean (Bank 1). Hello all, need some yota advice. I have a Po171 Fuel Trim Lean with slight power loss but not very noticable. MAF and O2 seem to be doing their job, no obviouse vacuum leaks however the fuel trim is off. Short term is always +/- 5 or so but the longterm chang...
May 11, 2006
1997 Mitsubishi Eclipse RS 2.0L Hesitation, Cuts out, MIL Lamp on VIN: 4A3AK34Y7V
P0171: Fuel System Lean (Bank 1). car came in for a check engine light on and intermitant stalling condition. just sitting here in the shop in park it will idle fine then every few minutes or so it acts like you turned the key off and back on real fast. it starts to stall then comes back and t...
May 13, 2006
1997 Mitsubishi Eclipse RS 2.0L Hesitation, Cuts out, MIL Lamp on VIN: 4A3AK34Y7V
P0171: Fuel System Lean (Bank 1). car came in for a check engine light on and intermitant stalling condition. just sitting here in the shop in park it will idle fine then every few minutes or so it acts like you turned the key off and back on real fast. it starts to stall then comes back and t...
May 15, 2006
1995 Saab 900 S 2.3L MIL Lamp on VIN: YS3DD58B8S
P0171: fuel trim max. value too lean. ... and ect signal. Verified ect O.L., replaced ect and thermostat. Smoke check intake, all O.K. threw P0171 again after t/drive and hot restart. Car claims OBDII compliance but generic scan tools can't communicate and TechII does not support freeze frame data...
May 17, 2006
2001 Ford F-150 XL 4.2L Poor Idle Quality, Cuts out VIN: 2FTZX17211
P0171: System lean bank 1. Fellow Techs, I have this 01 F150 that belongs to my nephew. A little history. He got the truck from his father in Ohio with the heads removed. It had been diagnosted by the dealer as a blown head gasket causing intermittent lean running problems. Was torn dow...
May 20, 2006
2001 Ford F-150 XL 4.2L Poor Idle Quality, Cuts out VIN: 2FTZX17211
P0171: System lean bank 1. Fellow Techs, I have this 01 F150 that belongs to my nephew. A little history. He got the truck from his father in Ohio with the heads removed. It had been diagnosted by the dealer as a blown head gasket causing intermittent lean running problems. Was torn dow...
May 21, 2006
2001 Ford Windstar LX 3.8L code 171 174 VIN: 2FMZA51431
P0171: lean exhaust bank 1. hey ford fans, i have a ton of ford windstars with codes po171 and po174. no vaccum leaks detected O2 seem to be responding well. also have town car with same problem. please help us we are head overheals with ohio e-checks. thank you
May 23, 2006
2001 Infiniti I30 3.0L Hesitation, MIL Lamp on
P0171: Fuel Trim Lean (Bank 1). ... on this one. The code sets in the morning. When I scan the MAF after it is hot, I get a 2.08 reading at 715 rpm in park and a 2.8 reading in drive at 650 rpm. I thought it should be higher at a higher rpm not reversed. Am I right? MAF problem? I know the M...
May 24, 2006
2004 Ford Crown Victoria 4.6L MIL Lamp on VIN: FAFP71W64X
P0171: System too lean Bank 1. Bank one too lean. This sets a code at 1800 rpm and 50 miles of driving. When cheking data stream in shop and driving the short term fuel trim is not lean but on the rich side. Seems like a fuel problem with fuel but cannot find a way to check fuel pressure si...
May 25, 2006
2003 Mitsubishi Montero Limited 3.8L MIL Lamp on VIN: JA4NW51S73
P0171: Fuel System Lean (Bank 1). ... '03 Montero that will set p0171. p0174 codes right away at idle. My fuel trims long and short get fixed at 12.5% long and 25% short term. If I add a small amount of propane, these ramp down to near normal. If I pinch off the fuel return line slightly, the ...
May 30, 2006
2001 Nissan Sentra GXE 1.8L MIL Lamp on VIN: 3N1CB51D21
P0171: Fuel Trim Lean. the car came in with code p0171 checked for exhaust leaks air intake leaks fuel pressure is ok 38 psi and 43 psi with regulator dissconnected maf checks out ok have mitchell info for code followed everything tests ok hopefully im just overlooking something
May 30, 2006
1996 Ford Contour GL 2.0L MIL Lamp on VIN: 1FALP6533T
P0171: system lean bank 1. HI FORD TECHS CAR GETS A PO171 ONLY AFTER DRIVING 72 MPH OR HIGHER. CAR HAS GOOD O2 READINGS GOOD BARO PID GOOD MAF READINGS THE ONLY FREEZE FRAME DATA THAT I DONT KNOW ABOUT IS FULSYS1 OL DRV DOES THIS MEAN FUEL SYSTEM 1 OPEN LOOP IN DRIVE? THE FREEZE FRAME D...
May 31, 2006