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P0171 Diagnostic Trouble Code Discussion for November 2009

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2004 Audi A8 Quattro L 4.2L Poor Idle Quality, MIL Lamp on VIN: WAUZZZ4E84
P0171: System Too Lean - Bank 1. This Audi A8 L Quattro will rough idle at cold start up for about [...] and during that time engine light will flash for about 15-20 seconds.Could not find any vaccum leaks.Please help. Thank You
November 01, 2009
2001 BMW 740iL 4.4L MIL Lamp on VIN: WDBAGH8349
P0171: system lean b 1. ... test.Had above codes,checked rear intake crank case breather cover,& found it leaking,removed intake ,cleaned,and replaced intake rear cover and intake gaskets.Also checked cam sensors,right sensor ohmed open.also replaced right cam sensor.After cleari...
November 02, 2009
2000 Ford Focus SE 2.0L MIL Lamp on, lean VIN: 1FAFP36P3Y
P0171: lean. ... came in with a p0171 lean code and a p1233 fuel pump driver module off line code. my main concern for right now is the lean code, but maybe i should be more concerned with the communication code also. the following items have been checked and verified to b...
November 02, 2009
1999 Chevrolet Express 3500 7.4L Poor Idle Quality VIN: 1GBJG31J4X
P0171: Fuel Trim System Lean (Bank 1). This van came in with a surging idle. We can not get the codes to reset. It will intermittently idle down to 400 rpm and then idle up to 950 rpm. The o2 sensors will cycle from 65mv to 855 mv. It will also randomly miss on all cylinders with the counts never e...
November 03, 2009
2005 Honda Civic EX 1.7L MIL Lamp on VIN: 1HGEM2193S
P0171: Fuel System Too Lean. car came in with p0135, o2 sensor heater circuit fault b1s1,customer stated fuel mileage was terrible, scanner read, heater circuit fault, "yes" check power & ground to heater circuit OK. replaced sensor. (very expensive sensor, by the way!) cleare...
November 03, 2009
2004 Volkswagen Passat GLX 4 Motion 2.8L MIL Lamp on VIN: WVWPD63B24
P0171: fuel trim too lean bank 1 no signal/no communication. ok gentlemen, here i have a 2004 passat. has multiple codes as you can see from above. the air filter is ok. there are no visible external vaccum/boost leaks that i can see using a smoke machine. the MAF is reading 0.0 grams per second at any rpm. it appears s...
November 03, 2009
2005 Honda Civic EX 1.7L MIL Lamp on VIN: 1HGEM2193S
P0171: Fuel System Too Lean. car came in with p0135, o2 sensor heater circuit fault b1s1,customer stated fuel mileage was terrible, scanner read, heater circuit fault, "yes" check power & ground to heater circuit OK. replaced sensor. (very expensive sensor, by the way!) cleare...
November 04, 2009
1996 Honda Accord EX 2.2L Poor Idle Quality, Misfire, MIL Lamp on VIN: 1HGCD5652T
P0171: Fuel System Too Lean (Bank 1). thanks for any help in advance and here are the vehicle symptoms: when car is first started(cold soak) engine runs fine but once it goes into closed loop idle gets a little rough but not misfiring then as soon as it is put in gear and a little load applied eng...
November 05, 2009
2003 Mini Cooper S 1.6L MIL Lamp on VIN: WMWRE33483
P0171: Lean bank 1. ... the check engine light came on and the car lacked power. Also said there was a rubber burning smell. They were using cruise control. I picked up the car and the light was off and the car ran great. Stopped and checked the old code and it was a P0171 lean ...
November 05, 2009
2002 Subaru Forester 2.5L MIL Lamp on VIN: JF1SG63673
P0171: Fuel System Too Lean (Bank 1). po171/po130 codes. checked fuel pressure, vac leaks ok. monitored ect,map,iat all within specs. b1s1 afr stays at 3.8v+, i think it should be .85-1.1v. post cat 02 reads rich at time but can be driven lean. afr does not change.Fuel trim with 1st new sensor rea...
November 05, 2009
1999 Chevrolet Express 3500 7.4L Poor Idle Quality VIN: 1GBJG31J4X
P0171: Fuel Trim System Lean (Bank 1). This van came in with a surging idle. We can not get the codes to reset. It will intermittently idle down to 400 rpm and then idle up to 950 rpm. The o2 sensors will cycle from 65mv to 855 mv. It will also randomly miss on all cylinders with the counts never e...
November 06, 2009
2002 Lincoln LS 3.0L Poor Idle Quality, Surge, Misfire VIN: 1LNHM86SX2
car was brought in for chugging and miss fire had 121,000. replaced plugs and fuel filter cleared computor road tested returned. two days car returned with same chugging problem. replaced downstream o2 bank 2. this time a week later same problem. found vaccume...
November 07, 2009
2006 Chevrolet Tahoe 5.3L No Start, Poor Idle Quality, Hesitation, Stall, Misfire, MIL Lamp on VIN: 5450673541
P0171: Fuel Trim System Lean (Bank 1). this goes out to fleet techs. We've been getting hard start with only E85 fuel vehicles only. Short term fuel at 3% long term is at 25%. Hard starting is cold only at below 40F fuel preasure is at 62psi at key on first cycle injector flow is even across the bo...
November 09, 2009
2004 Ford Ranger Edge 4.0L Poor Idle Quality, Surge, Cuts out, Stall VIN: FTREDSDEF4
Hey guys got this ranger came in with codes po171,174,720,722,cleared them ran truck,run good then goes into a spell wont run good wont rev up,check codes po1000,720,722,clear the codes then runs fine,acts up again codes are back,clear runs fine,any ideas?NOT ...
November 12, 2009
1998 Volkswagen Jetta GLX 2.8L p0171 VIN: 3VWTD81H6W
P0171: System too lean VAG Code16555. ... numerous service items and with a 'Check Engine' light on and numerous codes related to the need for a number of the items below being replaced. It appears this vehicle had not received regular maintenance, except for regular oil changes in the last 30k mi...
November 13, 2009
2002 Ford Ranger Edge 4.0L Hesitation, Cuts out, MIL Lamp on VIN: 1FTZR45E12
P0171: Lean Bank 1. Hi everybody and thanks in advance for your help. This vehicle idles OK but when accelerate sputters, hesitates and fuel trims go up to -23 B1 and -20 B2 MAF 54.26 gm/s with 2.88 V. and the codes listed below. I installed a NAPA MAF sensor, no change, found fu...
November 14, 2009
1999 Ford Expedition Eddie Bauer 5.4L MIL Lamp on VIN: 1FMRU17LXX
P0171: b1s1 lean. vehicle came in with p0131 o2 volts low, 171 and 174 lean b1/b2. found b1 sensor unplugged. plugged it in, scanned, found lt trim b1/b2 +20% idle and +5-7% at 2500rpm's. maf read 4.6 KPa at idle. smoked system, found iac and pcv actively leaking. replaced maf,...
November 15, 2009
2000 Daewoo Lanos S 1.6L Cuts out, Stall VIN: KLATA5268Y
P0171: system lean. ... no start towed vehicle in and almost didnt locate pressure spec. vehicle requires 41-47 psi pressure replaced original pump as it produced 0 pressure first replacement installed and produced 44 psi let vehicle go and had to tow it back after about 10 days ...
November 18, 2009
2008 Dodge Caliber SXT 2.0L MIL Lamp on VIN: 1B34B48B68
P0171: system to lean b1. Hi, got a strange issue with fuel trim values on this caliber. Sets system to lean P171 code. Cleared trim values and under light acceleration you can watch short term trim count upto 25% until in brings long term near 20-25% range. Is trying to add fuel at id...
November 18, 2009
1997 Ford Explorer Eddie Bauer 4.0L Cuts out VIN: 1FMDU34E3V
P0171: system lean. idles& runs good except for what sounds like backfire in intake manifold. fuel trims whent from +23 to +5 at idle after intake manifold gaskets replaced. any problems with cracks in plastic in. manifolds? still sounds like vac. leak on tipin. fuel trims +5...
November 24, 2009
2000 Kia Sportage 2.0L MIL Lamp on VIN: KNDJB72341
P0171: Fuel System Too Lean (Bank 1). this truck has alot of new sensores on it came from another shop has a code of po171 truck runs good i cleard the code and test drove got on the freeway lite came on same code could this have bad injectors i havent check fuel yet runs to good to be runing out ...
November 24, 2009