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P0171 Diagnostic Trouble Code Discussion for February 2011

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2001 Chevrolet Blazer LT 4.3L MIL Lamp on VIN: 1GNDT13W21
P0171: Fuel System Lean (Bank 1). Ok , this truck is a PROBLEM. I have lean codes on both banks. the fuel trims climb instantly when reset (cold 18-20%) once in closed loop 18-20% til long term hit 10-15 then short goes to 2-5. I know this has to be a common component that effect both bank. so...
February 01, 2011
2005 Chevrolet Workhorse 4.8L No Start VIN: 5B4HP42V15
P0171: fuel trim lean bank 1. Truck has repeatedly left the driver sitting and later restarts, it was towed in during a freezing rain storm in a no start condition.When we went to get the truck out of the lot (on a dry day) it started runs fine data stream looks normal.Have performed wiggl...
February 03, 2011
2005 Ford F-150 XL 4.2L No Start VIN: 1FTRF12265
P0171: syst bnk 1 too lean. help! im tossed in the middle of it again! towed in, cranks, no start. multiple dtc's, replaced cam sensor, fuel pressure @ rail is 40-42psi, raw fuel out of exhaust, spark @ all 6 towers on coil. cam/crank show in sync. found 5 volts for the imrc data pid. ha...
February 03, 2011
2004 Audi A4 1.8L Hesitation, MIL Lamp on VIN: WAUJC68EX2
P0171: system too rich bank 1. Car running poorly check engine light on. Found 5 DTC"s Tested o2 sensor/ A/F sensor heater working and sensor working. Cooling fan stays on all the time. Found Identifix bulletins leading to Leak detection pump(LDP). LDP is not receiving power tested fuel...
February 04, 2011
2001 Toyota 4Runner Limited 3.4L MIL Lamp on VIN: JT3HN87R4X
P0171: Fuel System Too Lean (Bank 1). ... 4-runner customer drove truck 4 weeks and the P0171 has returned(800 miles). did my investigation of the system and it seems it only runs one bank controls, meaning it does not have a bank 2 system. there is a up stream O2 and a down stream O2. the up stre...
February 04, 2011
2003 Jaguar X-Type 2.5L Hesitation, Cuts out VIN: SAJEA51D53
P0171: bank1 lean. ... complaint of a check eng light. We found p0171 and p0174.Ltft's were both 19.5. We found the original fuel filter, so we replaced it and flushed the injectors with our motorvac system, we smoke tested for vacuum leaks and no...
February 07, 2011
2003 Jaguar X-Type 2.5L Hesitation, Cuts out VIN: SAJEA51D53
P0171: bank1 lean. ... complaint of a check eng light. We found p0171 and p0174.Ltft's were both 19.5. We found the original fuel filter, so we replaced it and flushed the injectors with our motorvac system, we smoke tested for vacuum leaks and no...
February 08, 2011
1996 Dodge Dakota 3.9L No Start, Poor Idle Quality, Misfire VIN: 1B7GG23X6T
P0171: Fuel System Lean (Bank 1). Truck came in for hard start. initially fount coolant temp on scan tool reading 290 when cold. unplugged sensor no change. started messing with wiring and it initially dropped to -40 then went to 22, suspected wiring issue but after testing and retesting found...
February 09, 2011
1999 Jaguar XJ8 4.0L Excessive Emissions, Hesitation, MIL Lamp on VIN: SAJHD1045X
P0171: System lean bank 1. ... light on P0171 and P0174. Smoke test intake and found PCV hoses leaking and quick disconnect for brake booster. Replace O-ring in quick disconnect and replace both PCV hoses, intake gaskets and install new spark plugs. Recheck for leaks with smoke tester -...
February 09, 2011
2006 Chevrolet Trailblazer EXT LS 4.2L MIL Lamp on VIN: 1GNDT13S86
P0171: Fuel System Lean (Bank 1). ... found p0171 in history. check for vacuum leaks(smoke check), checked for 02 response responded quickly for forced rich(carb cleaner) test drove with fuel pressure gauge attached and found no problems. Did notice maf to be at 6gm/second at idle and thought ...
February 14, 2011
1999 Jaguar Vanden Plas 4.0L Excessive Emissions VIN: SAJKX604XX
P0171: System too leak Bank 1. P-0171 & P-0174 appeared after replacing throttle body for P-0121 code with a remanufactured one from BBA Reman (this was not the original one remanned by them but one off the shelf.) Performed BBA's recommended re-learn procedure & thottle body code h...
February 14, 2011
1999 Jaguar Vanden Plas 4.0L Excessive Emissions VIN: SAJKX604XX
P0171: System too leak Bank 1. P-0171 & P-0174 appeared after replacing throttle body for P-0121 code with a remanufactured one from BBA Reman (this was not the original one remanned by them but one off the shelf.) Performed BBA's recommended re-learn procedure & thottle body code h...
February 15, 2011
2003 Toyota Highlander 2.4L MIL Lamp on VIN: JTEGD21A53
P0171: Fuel System Too Lean (Bank 1). Hey guys, I've got a good one. This 03 highlander has a couple of problems. According to the scanner this vehicle is running very lean ... 24% short term fuel trim (after being reset) and the long term follows it. I have checked the MaF which is clean, fairly ...
February 15, 2011
2000 Ford Explorer XLT 4.0L Cuts out, Stall, MIL Lamp on VIN: 1FMDU72X9Y
P0171: Fuel system lean B1. ... been setting codes P0171 & P0174 even after intake gaskets been replaced, and reman Maf sensor, but was not having any other driveability concerns, lately customer complaints that truck stalls when shift to Reverse o...
February 16, 2011
2005 Audi A4 Quattro 1.8L Poor Idle Quality, Misfire, MIL Lamp on VIN: WAULC68E45
P0171: Fuel trim B1 lean. Howdy techs, this one will just not go away. About 6 weeks ago, put a used engine in this car(w/new turbo). Had lost oil pressure, had numerous codes: knock sensor controls, misfires, cam timing. 2 weeks later, intermittant misfire codes came back, had coils r...
February 17, 2011
2003 Ford E-250 5.4L Misfire VIN: 1FTNS24L53
P0171: bnk 1 too lean. thron into the mix on this e250, has cyl 1 misfire, customer claims it misses all the time and its just awful. lol. it doesnt miss all the time, occasionally at idle. have not found any vac leaks, cannot get it to misfire enough to diag it. anyone else seen th...
February 17, 2011
2006 GMC Envoy XL Denali 5.3L MIL Lamp on, Mis-fire VIN: 1GKET16S26
P0171: Fuel System Lean (Bank 1). ... 4.2L inline six cylinder.(not a Denali) came in with CEL. Ran codes with SOLUS-Pro scan tool. DTC-P0300 is the one I can't solve. I have a intermittent misfire on cyl # 4 & #6. I replaced all six spark plugs. Still had the same results. Then I swapped ...
February 17, 2011
2007 Toyota RAV4 3.5L MIL Lamp on VIN: JTMBK31V77
P0171: Fuel System Too Lean (Bank 1). Lean codes P0171 and P0174 set usually around 170 to 180 degrees during warm up. No vacuum leaks found with smoke machine 2 times. Fuel pressure in spec (44-47 psi). Did diagnositics for codes per All Data. Unable to find problem. Air Flow sensors operate in r...
February 17, 2011
2007 Toyota RAV4 3.5L MIL Lamp on VIN: JTMBK31V77
P0171: Fuel System Too Lean (Bank 1). Lean codes P0171 and P0174 set usually around 170 to 180 degrees during warm up. No vacuum leaks found with smoke machine 2 times. Fuel pressure in spec (44-47 psi). Did diagnositics for codes per All Data. Unable to find problem. Air Flow sensors operate in r...
February 18, 2011
2001 Nissan Pathfinder LE 3.5L Hesitation, MIL Lamp on VIN: JN8DR09Y11
P0171: Fuel Trim Lean (Bank 1). ... a state inspection because of a P0171 code.Truck ran fine when it came in,did a relearn and it ran like crap till the code reset.I cleaned the MAF with no luck.So I then replaced MAF seeing that they are a problem child with this vehicle.As soon as you tou...
February 22, 2011
2000 Toyota Corolla VE 1.8L Excessive Emissions, Hesitation VIN: 2T1BR12E3Y
P0171: Fuel System Too Lean (Bank 1). The car has failed emissions and has bad hesitation. Its like it has a dead spot in the throttle response between 10 and 50 percent throttle. I have run all component tests on this car, checked o2 sensor 1, MAF sensor, TPS sensor, MAP sensor. no vacuum leaks, ...
February 22, 2011
2000 Toyota Corolla LE 1.8L Poor Idle Quality, Stall, Misfire, MIL Lamp on, Hard Start VIN: 1NXBR12E2Y
P0171: Fuel System Too Lean (Bank 1). Ran excellent after repairs, but no starts very rough. Vacuum readings unstable at idle, wondering if severe vacuum leak is the direction I should head, know problem w/ intake gaskets on these. Possibly a lack of fuel however, injectors maybe. Vehicle also has...
February 23, 2011
2000 Toyota Corolla VE 1.8L Excessive Emissions, Hesitation VIN: 2T1BR12E3Y
P0171: Fuel System Too Lean (Bank 1). The car has failed emissions and has bad hesitation. Its like it has a dead spot in the throttle response between 10 and 50 percent throttle. I have run all component tests on this car, checked o2 sensor 1, MAF sensor, TPS sensor, MAP sensor. no vacuum leaks, ...
February 23, 2011
2005 Pontiac Vibe 1.8L MIL Lamp on VIN: 5YSL63855Z
P0171: Fuel Trim System Lean. ... back for MIL on, code p0171-system lean. The intake system passed smoke test, I cleaned the air flow sensor and replaced upstream O2 sensor with OE part. Should we look at replacing the air flow sensor or look elsewhere first? It has the 1zz-fe with Califo...
February 25, 2011
2006 GMC Sierra 1500 HD SLE 6.0L MIL Lamp on VIN: 1GTGK13U56
P0171: Fuel Trim System Lean (Bank 1). customer had code po101 stored so he replaced mass air flow sensor and cleared code. code came back with two other codes. po171 and po 174 left and right banks fuel trim lean. we hooked up scan tool and tried to clear codes. codes would not clear. found air in...
February 28, 2011