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P0171 Diagnostic Trouble Code Discussion for December 2011

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2002 Lincoln LS 3.0L Poor Idle Quality, Stall VIN: 1LNHM86S22
P0171: Lean bank one. We have a very intermittant idle issue with this car. In the morning it is driven app. 15 miles then while idleing to drop kids at school it will stumble once about every five minutes and about once a week when it does this it will die and start right back up....
December 01, 2011
2008 Chevrolet Colorado LT 3.7L Poor Idle Quality, VIN: 1GCDT13E68
P0171: Lean a/f condition. Teh truck runs fine on cold start and driving. After the engine has been warmed up and shut off for 2 hours on restart the engine idle is very rough and low for about 1 minute [feels like engine is flooding] we have smoke tested intake manifold for leaks remov...
December 02, 2011
2003 Chevrolet Suburban 2500 LS 6.0L MIL Lamp on VIN: 3GNGC26U53
P0171: Fuel Trim System Lean (Bank 1). At idle the long term trim is 0 to 2. The O2 sensors cycle rich and lean correctly. With my Genisys reading long term trim on a test drive, the LT trim goes up to 25 on both banks after accelerating for 4 seconds. It goes back down when you stop accelerating t...
December 06, 2011
2002 Chevrolet Silverado 1500 4.8L Cuts out, Misfire, MIL Lamp on VIN: 1GCEC19V02
P0171: Fuel Trim System Lean (Bank 1). we have changed both o2 sensors, mass air flow, intake manifold gasket, fuel filter, injectors and fuel pressure regulator.
December 07, 2011
2007 Chevrolet Equinox LS 3.4L MIL Lamp on VIN: SCREAM1NG7
P0171: Fuel Trim System Lean (Bank 1). We need help with an ongoing problem with the equinox,on the last go around we replaced the rear O2 sensor.Several wierd things I dont get.Previously the data stream showed no signal fron the MAF , Air temp, or coolant temp sensor.Later they seem to working OK...
December 07, 2011
2005 Ford F-150 FX4 5.4L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1FTPX14525
P0171: Bank 1 system lean. ... via instrument cluster shows normal and engine doesnt make much noise other than the horrible misfires but havent checked with guage yet. Watching varaible cam timing on genysis scan tool shows 65% adv error on bank 2 and only .06% on bank 1. Original pull...
December 07, 2011
2001 Lincoln LS 3.0L Misfire, Runability VIN: 1LNHM86S31
P0171: System too lean bank 1. Hello Lincoln Techs thanks in advance for your help this 3.0 v 6 has me pulling my hair out by the roots. After repairing a massive vacuum leak under the intake this vehicle's battery was disconnected with positive and negative battery touched together to rese...
December 07, 2011
1997 Chevrolet C1500 Cheyenne 5.7L MIL Lamp on VIN: 1GCEC19R7V
P0171: Fuel Trim System Lean (Bank 1). I'm hoping someone can shed some light on the problem I am having with this truck. I believe the problem is fuel pressure related. First off,I have checked thoroughly for vacuum leaks and found none. The MAF has been replaced with a known good part with no imp...
December 08, 2011
2005 Ford F-150 FX4 5.4L Poor Idle Quality, Hesitation, Surge, Cuts out, Stall, Misfire, MIL Lamp on VIN: 1FTPX14525
P0171: Bank 1 system lean. ... via instrument cluster shows normal and engine doesnt make much noise other than the horrible misfires but havent checked with guage yet. Watching varaible cam timing on genysis scan tool shows 65% adv error on bank 2 and only .06% on bank 1. Original pull...
December 08, 2011
2001 Toyota Corolla CE 1.8L Hesitation, Cuts out VIN: 1NXBR12E11
P0171: Fuel System Too Lean (Bank 1). ... started working on it. Noticed p0171 but customer wasn't interested in looking into it. Replaced valve cover gasket and air filter as requested, then cleaned engine bay. After that, drove and noticed it falls flat on it's face when accelling more than 15% ...
December 10, 2011
2001 Toyota Corolla CE 1.8L Hesitation, Cuts out VIN: 1NXBR12E11
P0171: Fuel System Too Lean (Bank 1). ... started working on it. Noticed p0171 but customer wasn't interested in looking into it. Replaced valve cover gasket and air filter as requested, then cleaned engine bay. After that, drove and noticed it falls flat on it's face when accelling more than 15% ...
December 11, 2011
1998 Ford Ranger Splash 2.5L Excessive Emissions, Poor Fuel Economy, MIL Lamp on VIN: 1FTYR10C4W
P0171: B1 Lean. This truck has a P0171 stored, fuel trims as noted. Trims clear out off idle and while driving. Behaves like a normal vacuum leak. Disconnected all vacuum, breather, and PCV hoses and lines and capped them off. No change. Looked for gasket leaks with propane. ...
December 12, 2011
2003 Land Rover Discovery SE 4.6L MIL Lamp on VIN: SALTY16413
P0171: Bank 1 Lean. Normally, these faults are a sure sign of a failed MAF. However, the problem has re-occurred after a while after multiple MAF replacements. Through all of this, the truck runs and drives fine, but we can't seem to get the faults to go away. Anyone else run...
December 12, 2011
2000 Pontiac Grand Prix GT 3.8L MIL Lamp on VIN: 1G2WP52K7Y
P0171: Fuel System Lean. have this car that gets +16% ltft at idle and -18% ltft while driving. it started with a positive ltft at all driving conditions. fuel system pressure test revealed a faulty fpr (low system pressure). we replaced the fpr. and also replaced valve cover gasket...
December 12, 2011
1998 Ford Ranger Splash 2.5L Excessive Emissions, Poor Fuel Economy, MIL Lamp on VIN: 1FTYR10C4W
P0171: B1 Lean. This truck has a P0171 stored, fuel trims as noted. Trims clear out off idle and while driving. Behaves like a normal vacuum leak. Disconnected all vacuum, breather, and PCV hoses and lines and capped them off. No change. Looked for gasket leaks with propane. ...
December 13, 2011
2002 BMW 325Ci 2.5L MIL Lamp on VIN: WBABN33442
P0171: lean. Good day, this engine is running lean on both banks off idle. At idle, stft is ranging from -2% - +2% on both banks. ltft is at 11.7% both banks. At cruising speeds, stft ranges from 10%-18% both banks. ltft has never changed and again is at 11.7%. The MAF, sn...
December 14, 2011
2001 Dodge Dakota 3.9L MIL Lamp on VIN: 1B7GL22X71
P0171: Fuel System Lean (Bank 1). Reset check eng light test drove pending code comes back on after driving for a minute.. Check 02 sensors are switching normally engine runs fine all the time it only die once on me when it was cold from park to drive it die and restarted right away and has no...
December 15, 2011
2001 Nissan Frontier XE 2.4L Poor Fuel Economy, MIL Lamp on VIN: 1N6DD26S91
P0171: Fuel Trim Lean (Bank 1). hello fellow iatn members,we have a 2001 Nissan frontier, 2.4L, 5 speed, manual trans. the truck runs fine, good, strong, but keeps setting dtc. po171, system too lean, bank one. as you can see, emissions are clean, we have no vacuum leaks, good fuel pressure,...
December 18, 2011
2008 Audi A3 2.0L Stall, MIL Lamp on VIN: WAUHF68PX8
P0171: Fuel Trim Bank 1 - System too lean. Dear Audi Friends: We service car since new and it always was a good car, now it came in with 4 (9) faults. see above. Customer complain is: in the morning (only) car will start stall multiply times, to get car idling you have to depress accel pedal and car st...
December 20, 2011
2001 Infiniti G20 2.0L Hesitation, Cuts out, MIL Lamp on VIN: JNKCP11A31
P0171: Fuel Trim Lean (Bank 1). car came in for emission code P0171-P0172 replaced the O2 and Mass air flow sent the car out to be reprogramed went to get a drive cyle and could not pass CAT O2 AND EVAP. ran compresion 150 all cyls. tested tps exhast back pressure Ok now car will not rev up ...
December 20, 2011
2001 Ford Expedition XLT 5.4L Poor Idle Quality VIN: 1FMRU15L01
P0171: rich bank 1. i wrote the details on repair history ifeel as if its electrical but what shaked wires conectors etc. i feel like theres somthing in common with the 1-4 cylinders on mode 6 does not show any failing cylinders or coils
December 27, 2011
2003 Ford Explorer Eddie Bauer 4.6L MIL Lamp on VIN: 1FMZU74WX3
P0171: Lean bank 1 long term around 25. ... keeps setting a presistent p0171 and p0174 the fuel trims are both positive bank one around +25 bank 2 is around +21. Both get worse when engine is reved up. Bank 1 o2 was slow so I replaced it. I have smoked it several times and sprayed no smoked and no c...
December 29, 2011
2006 GMC Envoy XL SLE 4.2L Poor Fuel Economy, MIL Lamp on VIN: 1GKET16S56
P0171: Fuel System Lean (Bank 1). I have some confusion the dealership is saying the coolant temperature sensor for the guage is located right rear behind the engine of cylinder head, however there is the coolant temperature sensor shows same part number but is there two of them and where are ...
December 30, 2011
2006 GMC Envoy XL SLE 4.2L Poor Fuel Economy, MIL Lamp on VIN: 1GKET16S56
P0171: Fuel System Lean (Bank 1). I have some confusion the dealership is saying the coolant temperature sensor for the guage is located right rear behind the engine of cylinder head, however there is the coolant temperature sensor shows same part number but is there two of them and where are ...
December 31, 2011