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P0171 Diagnostic Trouble Code Discussion for October 2006

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
1999 Toyota Sienna CE 3.0L MIL Lamp on VIN: 4T3ZF19C1X
P0171: Fuel System Too Lean (Bank 1). thanks in advanced - the front o2 or air/fuel sensors - are they supposed to switch like a normal o2 the only variance was from .65 - .64 i have cleaned the air flow sensor & checked for vacuum leaks. is there any test that can be done to it, before replac...
October 04, 2006
2000 GMC Jimmy Diamond Edition 4.3L Excessive Emissions, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1GKDT13WXY
P0171: Fuel System Lean (Bank 1). Hello all,I am posting this truck again. I was closing the original and the cust. called.Same condition and codes.It took 2wks and 300mi to act up. I am including the original post& up date. Also, when acting up, B1S1 O2 is at 890mv on DVOM while scan data...
October 05, 2006
2000 Toyota Celica GT 1.8L Hesitation, MIL Lamp on VIN: JTDDR32T6Y
P0171: Fuel System Too Lean (Bank 1). Toyota Techs please help. Car came in with MIL on for Lean condition. We inspected for vacuum leaks and found none. MAF sensor seems to be operating properly. If you open the throttle quickly the engine dies for a second and then picks up speed normally. It a...
October 06, 2006
2000 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF28B4Y
P0171: Fuel System Too Lean (Bank 1). Car came back after 3 days with PO171 present.Engine runs greate,plenty of power.Can't locate external vacuum leaks. I hear hissing sound around air bypass valve at idle. When I clamp a hose connected to AIR BYPASS VALVE which collects a vacuum from bank1 and ...
October 10, 2006
2003 Ford Expedition XLT 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FMRU15W13
P0171: fuel system lean bank 1. ... try to supply it. The first tech gave up and now its my turn. The truck runs fine down the road. The problem is only noticable at idle (which is rough/but stable). The mil light is/was on with two codes, P0171-lean bank 1,...
October 12, 2006
2001 Volkswagen EuroVan MV 2.8L MIL Lamp on VIN: WV2MB47001
P0171: bank 1 fuel measuring system system to lean. ... euro van has 1 code always p0171 system to lean. I have done everything under corretive actions from bently and chiltons. ck fuel psi and delivery on the money 36 with vac 42 with out. smoke ck this car many times I find nothing. also about 1 qt off fuel i...
October 12, 2006
1998 Ford Explorer Eddie Bauer 4.0L Surge, MIL Lamp on VIN: 1FMZU34E2W
P0171: bnk 1 lean. Hey Ford guys, this Exploder has fuel trims at idle at +20% on the short term, and -20% on the long term. This seems strange to be this way, but who knows on a Ford. I hear a vacuum leak, and I know how sensitive Ford's are to leaks like that. This has a plast...
October 13, 2006
2004 Chevrolet Trailblazer EXT LT 4.2L Poor Fuel Economy, MIL Lamp on VIN: 1GNET16S94
P0171: Fuel System Lean (Bank 1). Vehicle has been here 3 times for same codes. First time we sent customer to Dealer for reprogram. Replaced [...] next two times. Fuel pressure is 47 psi(ok per shopkey). Was told by OEM parts dept that this eng does not have a PCV valve. Is anyone else having...
October 17, 2006
2002 Ford E-250 Econoline 4.2L MIL Lamp on VIN: 1FTNS24282
P0171: system too lean b1. this van has 4x currant DTC's witch seem to contradict themselves. were not sure what to do at this point. we have checked all the basics, listed. also checked for related TSB's. any help would be grand.
October 17, 2006
1999 Pontiac Grand Am SE 2.4L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1G2NE52T4X
P0171: Fuel System Lean. ... computers, coil cover fuel injection cleaning,fuel filter and extra 02 sensor ground at pin 21 of computer. pulled injectors out. and watched spray pattern out of car while cranking all looks good. this is a non egr engine. injector have been also ohm test...
October 17, 2006
1998 Ford Explorer Eddie Bauer 4.0L Surge, MIL Lamp on VIN: 1FMZU34E2W
P0171: bnk 1 lean. Hey Ford guys, this Exploder has fuel trims at idle at +20% on the short term, and -20% on the long term. This seems strange to be this way, but who knows on a Ford. I hear a vacuum leak, and I know how sensitive Ford's are to leaks like that. This has a plast...
October 18, 2006
1999 Lincoln Town Car Signature 4.6L MIL Lamp on VIN: 1LNHM82W9X
P0171: lean condition b1. ... codes p0171 &p0174 I did most of the commun fixes & cleaning but no luck Im thinking air flow meter
October 23, 2006
2000 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF28B4Y
P0171: Fuel System Too Lean (Bank 1). Car came back after 3 days with PO171 present.Engine runs greate,plenty of power.Can't locate external vacuum leaks. I hear hissing sound around air bypass valve at idle. When I clamp a hose connected to AIR BYPASS VALVE which collects a vacuum from bank1 and ...
October 25, 2006
2000 Chrysler Cirrus LXi 2.5L MIL Lamp on VIN: 1C3EJ56H3Y
P0171: Fuel System Lean. I have a car that seems to have a vacum leak but I am unable to find any.At an idle the LTFT is at +20%,off Idle it is at +20%.also the IAC valve is at 7on the counts.I smoked the intake to find any leaks and found none.Also checked the EGR valve to make sure ...
October 26, 2006
2001 Cadillac DeVille 4.6L Excessive Emissions, Poor Fuel Economy, MIL Lamp on VIN: 1G6KD54Y41
P0171: Fuel Trim System Lean (Bank 1). ... the time and it is a big help, as I am on my own now. Just bought this shop in the spring. I have an 01 Cadilac Deville in here that is just pooring the fuel through it. Has codes P0171 and P0174. From the local used car lot!!! ...
October 27, 2006
1999 Toyota Sienna CE 3.0L MIL Lamp on VIN: 4T3ZF19C1X
P0171: Fuel System Too Lean (Bank 1). thanks in advanced - the front o2 or air/fuel sensors - are they supposed to switch like a normal o2 the only variance was from .65 - .64 i have cleaned the air flow sensor & checked for vacuum leaks. is there any test that can be done to it, before replac...
October 04, 2006
2000 GMC Jimmy Diamond Edition 4.3L Excessive Emissions, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1GKDT13WXY
P0171: Fuel System Lean (Bank 1). Hello all,I am posting this truck again. I was closing the original and the cust. called.Same condition and codes.It took 2wks and 300mi to act up. I am including the original post& up date. Also, when acting up, B1S1 O2 is at 890mv on DVOM while scan data...
October 05, 2006
2000 Toyota Celica GT 1.8L Hesitation, MIL Lamp on VIN: JTDDR32T6Y
P0171: Fuel System Too Lean (Bank 1). Toyota Techs please help. Car came in with MIL on for Lean condition. We inspected for vacuum leaks and found none. MAF sensor seems to be operating properly. If you open the throttle quickly the engine dies for a second and then picks up speed normally. It a...
October 06, 2006
2000 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF28B4Y
P0171: Fuel System Too Lean (Bank 1). Car came back after 3 days with PO171 present.Engine runs greate,plenty of power.Can't locate external vacuum leaks. I hear hissing sound around air bypass valve at idle. When I clamp a hose connected to AIR BYPASS VALVE which collects a vacuum from bank1 and ...
October 10, 2006
2003 Ford Expedition XLT 4.6L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FMRU15W13
P0171: fuel system lean bank 1. ... try to supply it. The first tech gave up and now its my turn. The truck runs fine down the road. The problem is only noticable at idle (which is rough/but stable). The mil light is/was on with two codes, P0171-lean bank 1,...
October 12, 2006
2001 Volkswagen EuroVan MV 2.8L MIL Lamp on VIN: WV2MB47001
P0171: bank 1 fuel measuring system system to lean. ... euro van has 1 code always p0171 system to lean. I have done everything under corretive actions from bently and chiltons. ck fuel psi and delivery on the money 36 with vac 42 with out. smoke ck this car many times I find nothing. also about 1 qt off fuel i...
October 12, 2006
1998 Ford Explorer Eddie Bauer 4.0L Surge, MIL Lamp on VIN: 1FMZU34E2W
P0171: bnk 1 lean. Hey Ford guys, this Exploder has fuel trims at idle at +20% on the short term, and -20% on the long term. This seems strange to be this way, but who knows on a Ford. I hear a vacuum leak, and I know how sensitive Ford's are to leaks like that. This has a plast...
October 13, 2006
2004 Chevrolet Trailblazer EXT LT 4.2L Poor Fuel Economy, MIL Lamp on VIN: 1GNET16S94
P0171: Fuel System Lean (Bank 1). Vehicle has been here 3 times for same codes. First time we sent customer to Dealer for reprogram. Replaced [...] next two times. Fuel pressure is 47 psi(ok per shopkey). Was told by OEM parts dept that this eng does not have a PCV valve. Is anyone else having...
October 17, 2006
2002 Ford E-250 Econoline 4.2L MIL Lamp on VIN: 1FTNS24282
P0171: system too lean b1. this van has 4x currant DTC's witch seem to contradict themselves. were not sure what to do at this point. we have checked all the basics, listed. also checked for related TSB's. any help would be grand.
October 17, 2006
1999 Pontiac Grand Am SE 2.4L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1G2NE52T4X
P0171: Fuel System Lean. ... computers, coil cover fuel injection cleaning,fuel filter and extra 02 sensor ground at pin 21 of computer. pulled injectors out. and watched spray pattern out of car while cranking all looks good. this is a non egr engine. injector have been also ohm test...
October 17, 2006
1998 Ford Explorer Eddie Bauer 4.0L Surge, MIL Lamp on VIN: 1FMZU34E2W
P0171: bnk 1 lean. Hey Ford guys, this Exploder has fuel trims at idle at +20% on the short term, and -20% on the long term. This seems strange to be this way, but who knows on a Ford. I hear a vacuum leak, and I know how sensitive Ford's are to leaks like that. This has a plast...
October 18, 2006
1999 Lincoln Town Car Signature 4.6L MIL Lamp on VIN: 1LNHM82W9X
P0171: lean condition b1. ... codes p0171 &p0174 I did most of the commun fixes & cleaning but no luck Im thinking air flow meter
October 23, 2006
2000 Toyota Avalon XL 3.0L MIL Lamp on VIN: 4T1BF28B4Y
P0171: Fuel System Too Lean (Bank 1). Car came back after 3 days with PO171 present.Engine runs greate,plenty of power.Can't locate external vacuum leaks. I hear hissing sound around air bypass valve at idle. When I clamp a hose connected to AIR BYPASS VALVE which collects a vacuum from bank1 and ...
October 25, 2006
2000 Chrysler Cirrus LXi 2.5L MIL Lamp on VIN: 1C3EJ56H3Y
P0171: Fuel System Lean. I have a car that seems to have a vacum leak but I am unable to find any.At an idle the LTFT is at +20%,off Idle it is at +20%.also the IAC valve is at 7on the counts.I smoked the intake to find any leaks and found none.Also checked the EGR valve to make sure ...
October 26, 2006
2001 Cadillac DeVille 4.6L Excessive Emissions, Poor Fuel Economy, MIL Lamp on VIN: 1G6KD54Y41
P0171: Fuel Trim System Lean (Bank 1). ... the time and it is a big help, as I am on my own now. Just bought this shop in the spring. I have an 01 Cadilac Deville in here that is just pooring the fuel through it. Has codes P0171 and P0174. From the local used car lot!!! ...
October 27, 2006