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P0171 Diagnostic Trouble Code Discussion for March 2013

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
1999 Chevrolet Tahoe 5.7L Poor Idle Quality, Hesitation VIN: 3GNEK18RXX
P0171: Fuel Trim System Lean (Bank 1). Hello all, need some help here. Vehicle came in for poor performance. Determined #7 cylinder leakage through exhaust valve. Removed cylinder heads and found severly bent exhaust vavle, performed valve job and reinstalled. After repair we noticed it running n...
March 01, 2013
2002 BMW 330xi 3.0L MIL Lamp on VIN: WBAEW53492
P0171: bk 1 lean. this is my personal car and is under a restoration period.after replacement of all wear and tear. and usual known "lean" condition issues.i'm still leaning out.after a third smoke test,i am getting smoke from around disa valve and intake manifold.my qu...
March 03, 2013
2005 BMW X3 3.0i 3.0L MIL Lamp on VIN: WBXPA93445
P0171: Bank 1 lean. Customer complaining of oil usage and oil smoke out of tailpipe on start-up. Found no external leaks but ck engine light on with lean codes. I can remove oil filler cap and engine runs rough. I can cover hole up with my hand and has internal vacuum leak and en...
March 04, 2013
1996 Cadillac DeVille Concours 4.6L MIL Lamp on VIN: 1G6KF5294T
P0171: Fuel Trim System Lean (Bank 1). ... P0141, P0171, P0174, P0300, P0603, P1406, P1599. The EGR was open at idle and replace the B1S2 O2 sensor. Car no longer dies at idle but resets the P0171 and P0174 with extremely high fuel trims. Smoke tested intake and fo...
March 04, 2013
2002 Toyota Celica GT 1.8L MIL Lamp on VIN: JTDDR32T62
P0171: Fuel System Too Lean (Bank 1). this car run great,except for the idler when cold its revs to 2000 rpm then after it warms up come down.but my problem its the ck engine light keeps coming on.i replaced both oxegen sensors to no avail.i still get the same code for lean and cat threshold not b...
March 06, 2013
2004 Lincoln Navigator 5.4L MIL Lamp on VIN: 5LMFU28R64
P0171: Lean bank 1. ... the ever so common p0171 and p0174.I smoked the intake to start with and found the EGR valve leaking smoke.Now I know that's common on fords but how much of a leak is too much?The fuel pressure was at 15 psi which is way ...
March 07, 2013
2009 Chevrolet Equinox LS 3.4L MIL Lamp on VIN: 2CNDL13F49
car has all the codes mentioned. plugs wires were changed. customer says then check engine light comes on, the traction control light also comes on and looses power. i am thinking bad throttle body. did the testing as per all data. just wanted to see what othe...
March 08, 2013
2000 Toyota Corolla VE 1.8L MIL Lamp on VIN: 2T1BR12E2Y
P0171: Fuel System Too Lean (Bank 1). The car keeps coming back with p0171 code light goes on and off.looking for any help on this problem.
March 08, 2013
2002 Toyota Celica GT 1.8L MIL Lamp on VIN: JTDDR32T62
P0171: Fuel System Too Lean (Bank 1). this car run great,except for the idler when cold its revs to 2000 rpm then after it warms up come down.but my problem its the ck engine light keeps coming on.i replaced both oxegen sensors to no avail.i still get the same code for lean and cat threshold not b...
March 08, 2013
2009 Chevrolet Equinox LS 3.4L MIL Lamp on VIN: 2CNDL13F49
car has all the codes mentioned. plugs wires were changed. customer says then check engine light comes on, the traction control light also comes on and looses power. i am thinking bad throttle body. did the testing as per all data. just wanted to see what othe...
March 09, 2013
2003 Dodge Neon SE 2.0L MIL Lamp on VIN: 1B3ES26C43
P0171: Fuel System Lean (Bank 1). ... , this is a 03 dodge neon se THAT HAS BEEN ENGINE SWAPPED WITH A 2.4L TURBO SRT4 DRIVETRAIN.The car is all back to stock configuration but i am fighting a p0171 bank 1 lean code. In the morning stone cold the stft is climbing to 30% , once the car is war...
March 11, 2013
2000 GMC Savana 3500 5.7L MIL Lamp on VIN: 1GTHG35R2Y
P0171: Fuel Trim System Lean (Bank 1). I have lean codes for Bank 1 and Bank 2. Customer says the Van has died on him at times I have checked fuel pressure at filter pump is pushing 90 psi and also checked at regulator and the pressure was a little low at 47 replaced regulator and now pressure is 5...
March 11, 2013
2003 Dodge Neon SE 2.0L MIL Lamp on VIN: 1B3ES26C43
P0171: Fuel System Lean (Bank 1). ... , this is a 03 dodge neon se THAT HAS BEEN ENGINE SWAPPED WITH A 2.4L TURBO SRT4 DRIVETRAIN.The car is all back to stock configuration but i am fighting a p0171 bank 1 lean code. In the morning stone cold the stft is climbing to 30% , once the car is war...
March 12, 2013
2000 GMC Savana 3500 5.7L MIL Lamp on VIN: 1GTHG35R2Y
P0171: Fuel Trim System Lean (Bank 1). I have lean codes for Bank 1 and Bank 2. Customer says the Van has died on him at times I have checked fuel pressure at filter pump is pushing 90 psi and also checked at regulator and the pressure was a little low at 47 replaced regulator and now pressure is 5...
March 12, 2013
2003 Jaguar XJ8 4.0L Poor Idle Quality, MIL Lamp on VIN: SAJDA14C93
P0171: Too lean bank 1. ... fault code p0171-too lean b1. Smoke tested intake sys for vacuum leaks, found all crankcase ventilation lines were leaking a small amount at connections as well as resonance tube on intake tube was cracking away from intake tube to throttle body. Replaced ...
March 13, 2013
2003 Volkswagen Passat GLS 1.8L Misfire VIN: WVWVD63B13
P0171: Lean bank 1. Engine just started exhibiting a misfire at idle issue. No external vacuum leaks were found. Moving the coils around did not change any codes. Could hear what sounded like a vacuum leak coming from the pressure diverter valve. Removed it and found that the ins...
March 13, 2013
2007 Chevrolet Avalanche LTZ 5.3L Misfire VIN: 3GNFK12347
P0171: Fuel System Lean (Bank 1). ... cylinder when the computer commands 4-cylinder operation mode. Once it trips the code P0305, it won't command 4-cylinder operation and doesn't miss again. Not sure if you can feel the misfire when it acts up because it runs rougher on 4 cylinders. This is ...
March 14, 2013
1997 Buick Riviera 3.8L Stall VIN: 1G4GD2216V
P0171: Fuel System Lean. Car came in originally for a crank no start. Found injector number 4 stuck wide open causing hard start and misfire. Replaced two injectors and put a set of spark plugs in it. Car started and ran great. After car would sit for 3 hours it would have a long cran...
March 15, 2013
2003 Ford F-150 XL 4.2L Excessive Emissions, Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, Poor Fuel Economy, MIL Lamp on, Hard Start VIN: 1FTRF07263
P0171: Lean Bank 1. ... P0171, P0175, P0316, P0302, P0303, and P0305. Replaced plugs for those cylinders due to heavy oil fouling. Improvement, but still misfiring. Came back today running worse and the codes are similar to...
March 15, 2013
2004 Chevrolet Suburban 1500 LS 5.3L Poor Idle Quality, Misfire, MIL Lamp on VIN: 3GNEC16ZX4
P0171: Fuel Trim System Lean (Bank 1). Hi there, This vehicle has a miss on every cylinder on the driver's side. TSB's indicate a possible intake manifold gasket leak. I can't confirm the leak with any testing so I thought I would ask before tearing into it. What is the likelyhood that it is the pr...
March 20, 2013
1998 Toyota Corolla CE 1.8L MIL Lamp on VIN: 2T1BR18EXW
P0171: Fuel System Too Lean (Bank 1). This car consistantly sets a P0171 after a day of driving. There are no drivability symptoms but the long term fuel trim at idle is around 18.8 and while driving it will go as high as 29. We have checked it for vacuum and air leaks and found none warm or cold....
March 21, 2013
1999 Mercury Mountaineer 4.0L Poor Idle Quality, Hesitation, Surge, Misfire VIN: 4M2ZU54E4X
P0171: Bank 1 lean. Hello everyone. Have this mountaineer Im trying to sort out for our alignment man here at the shop. He put all parts listed on it and still not fixed. He says very intermittently while driving at 30 or above the power just drops off and misfires and sputters t...
March 23, 2013
2006 Hyundai Tucson GLS 2.7L Hesitation, Surge, Poor Fuel Economy VIN: KM8JN12D76
P0171: Fuel System Too Lean (Bank 1). We had replaced both upstream oxygen sensor based on proir codes for the heater circuts. Once we had a pair of operational oxygen sensors the they both started throwing lean codes. We then smoke tested for vacuum leaks and found the plenum to have leaks at the...
March 25, 2013
1999 Mercury Mountaineer 4.0L Poor Idle Quality, Hesitation, Surge, Misfire VIN: 4M2ZU54E4X
P0171: Bank 1 lean. Hello everyone. Have this mountaineer Im trying to sort out for our alignment man here at the shop. He put all parts listed on it and still not fixed. He says very intermittently while driving at 30 or above the power just drops off and misfires and sputters t...
March 25, 2013
1996 Dodge B3500 5.9L Excessive Emissions, Comunication VIN: 2B5WB35Z1T
P0171: Fuel System Lean (Bank 1). My Biggest Concern Right Now Is A Intermitent Loss Of Communication With PCM, Engine Does Not Stumble Or Stall But Randomly The Scanner Will Lose Comm. And Then Reestablish The Link Sometimes 10-15 Secondes Other Times 30 Seconds To Minute In Random Occurances...
March 26, 2013
2002 Ford Windstar SE 3.8L Poor Idle Quality, Misfire VIN: 2FMZA52472
P0171: system too lean bank 1. Vehicle will do different things at different times, The boss drove it first and said it was missing bad under a load, The next day I drive it and it only notice light misfires at idle, Cylinder contribution test shows random cylinder misfires across all cylin...
March 26, 2013
2008 Ford F-450 Super Duty XLT 6.8L Hesitation VIN: 1FDXF47Y48
P0171: lean bank 1. truck losses power , fuel pressure drops to 3-10 psi on hard accel using both mech. gauge and ford IDS. traced and checked all wiring from fuel pump too module on frame rail to pcm and inertia switch, all seems good, loaded wires with headlight ok. disconnecte...
March 26, 2013
2006 Land Rover LR3 SE 4.4L MIL Lamp on VIN: SALAD25456
P0171: Lean bank 1. ... from local shop that could not dignose or scan. code p0171 ltft1 10-14% ltft2 6-9%. Found pcv valve bad first and replaced. no change in fuel trims and kicked code pretty quick. Smoked intake found excessive smoke at egr. sprayed egr with cleaner and fuel ...
March 26, 2013
1995 Buick Riviera 3.8L Poor Idle Quality, Misfire VIN: 1G4GD22K3S
P0171: fuel trim lean. Vehicle came into the shop running very rough at idle. We hooked up scan tool and found the the stft 182 counts and ltft 149 counts with an o2 sensor reading of 13 MV. Idle smooths when propane is added to air stream and fuel trims come down with o2 reading in...
March 28, 2013
1996 Chevrolet Lumina 3.1L No Start, Poor Idle Quality, Surge, Stall, Misfire, MIL Lamp on VIN: 2G1WL52M0T
P0171: Fuel System Lean (Bank 1). This car came in just over a week ago for a surge/misfire issue. Car ran ok so we went to the plugs. Original plugs so they were changed, test drove and all was good? Cuat. picked up car made a couple blocks and the surge/misfire was back and the SES light cam...
March 28, 2013
2007 Chevrolet Avalanche LTZ 5.3L Misfire VIN: 3GNFK12347
P0171: Fuel System Lean (Bank 1). ... cylinder when the computer commands 4-cylinder operation mode. Once it trips the code P0305, it won't command 4-cylinder operation and doesn't miss again. Not sure if you can feel the misfire when it acts up because it runs rougher on 4 cylinders. This is ...
March 28, 2013
2006 Land Rover Range Rover Sport HSE 4.4L MIL Lamp on VIN: SALSF25476
P0171: fuel trim. we have tryed every thing please help it runs great but sets fuel trim codes every time with in 3 miles. or even at idle u can see short term trims at 3 to 5 posi long term bank 1 at 10 to 12 bank2 at 12 to 14 posi please help!!
March 28, 2013
1995 Buick Riviera 3.8L Poor Idle Quality, Misfire VIN: 1G4GD22K3S
P0171: fuel trim lean. Vehicle came into the shop running very rough at idle. We hooked up scan tool and found the the stft 182 counts and ltft 149 counts with an o2 sensor reading of 13 MV. Idle smooths when propane is added to air stream and fuel trims come down with o2 reading in...
March 29, 2013
2003 Volkswagen Passat GLS 1.8L Excessive Emissions, Poor Fuel Economy, MIL Lamp on VIN: WVWPD63B83
we smoked checked the intake system. the new vent valve diaphram was blown again. we replaced the diaphram again and it blew again. i found a collapsed vac hose to evap system. Does anyone know what would cause the vacuum vent valve to keep going bad? are the ...
March 29, 2013