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P0171 Diagnostic Trouble Code Discussion for May 2010

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2001 Ford Taurus SE 3.0L Poor Idle Quality VIN: 1FAFP53U12
P0171: lean bank one. Hi All this ford came in with mil on. Scanned and found fuel pressure koeoff 25 koeon 29 lbs. replace pump with airtex module, and filter, (pluged bad). after replacement pressure up to 45 koeoff and 39 to 40 koeon. all seemed well. Three days later it's bac...
May 01, 2010
1999 Chevrolet Express 3500 5.7L Hesitation, Cuts out, Stall VIN: 1GAHG39R9Y
P0171: Fuel Trim System Lean (Bank 1). This van came in with severe hesitation (had to be towed in). First thing I noticed was no check engine light even when performing bulb check (koeo). Checked codes and found what I listed. Also I should mention that with the hesitation was also severe backfire...
May 05, 2010
1998 Ford F-150 Lariat 5.4L Poor Idle Quality, Hesitation, MIL Lamp on VIN: 1FTRX07L5W
P0171: B1 lean. ... emmision test. The codes were a p0171 and p0174. I have had this problem before on this truck and had already replaced the pcv hose assy. I pulled the hose to check it and it was ok. One thing that is getting me is the vehic...
May 05, 2010
2007 Volkswagen Rabbit 2.5 2.5L MIL Lamp on VIN: WVWAR71K57
P0171: system too lean. Need some help finding this lean condition.At idle lamda is .953 and snap throttle it goes to 1.99.At idle O2 voltage is 1.380,MAF is 2.80 g/s,injector timing is 1.64 ms.I'm going to run some cleaner through injectors,and see if that helps.When I run the readi...
May 06, 2010
2002 Hyundai Accent GL 1.5L MIL Lamp on VIN: KMHCF35G62
P0171: lean bank one. Car is making me crazy! Between 23 and 29 miles of driving the car will set a lean code sensor 1. The short term fuel trim is around 0 all the time but the long term is plus 25. The 02 toggle as they should and the car runs good it just won't pass smog. the fu...
May 10, 2010
2001 Ford F-150 XLT 5.4L Hesitation, Cuts out VIN: 1FTRW08LX1
P0171: System lean bank 1. Came in for loss of power ender load the codes where in history cant get them to come back- i smocked system for any vacuum leaks none found- o2's reading ok along with fuel trims,temp ect. Checked cats for blockage the truck runs fine until you get on the gas...
May 11, 2010
2007 Ford Ranger XL 2.3L MIL Lamp on VIN: 1FTYR14D47
P0171: bank 1 system too lean. I have a ranger bought from auction, supposedly a repo with 1 previous owner. Alldatas flow chart is practically useless. I have a ltft of 25% and stft around 24%. This truck went to the dealer, they charged him 400. to reflash pcm and replace both o2s then th...
May 11, 2010
1997 Chevrolet K1500 Silverado 5.7L Hesitation, Cuts out, MIL Lamp on VIN: 2GCEK19R1T
P0171: Fuel Trim System Lean (Bank 1). this truck came to my shop because when you give it gas it does not rev up it stumbles and cuts out and sometimes dies the cam retard was at 20 degrees when it came in customer told me he replaced the engine and removed the distributor i removed the distributo...
May 12, 2010
2007 Ford Ranger XL 2.3L MIL Lamp on VIN: 1FTYR14D47
P0171: bank 1 system too lean. I have a ranger bought from auction, supposedly a repo with 1 previous owner. Alldatas flow chart is practically useless. I have a ltft of 25% and stft around 24%. This truck went to the dealer, they charged him 400. to reflash pcm and replace both o2s then th...
May 12, 2010
2000 Infiniti I30 3.0L Hesitation, Misfire VIN: JNKCA31AXY
P0171: Fuel Trim Lean (Bank 1). ... with shakes and runs rough - scanned it then and had misfire codes - after diag and research we replaced 6 coils and 6 spark plugs and it has ran good since. Customer brought it back today with hesitation under acceleration. We verified the concern - scann...
May 12, 2010
2001 Honda Civic LX 1.7L No Start, Poor Idle Quality, Cuts out, MIL Lamp on VIN: 2HGES16501
P0171: Fuel System Too Lean. ... twofold.It will run great for one to three days then it will hard start/no start and set the P0171.On arrival the vehicle had no a/c,brake light on,door locks inoperative,no key dinger,overhead light and the intermittant no start w/ P0171.The flow chart on...
May 13, 2010
1997 Chevrolet K1500 Silverado 5.7L Hesitation, Cuts out, MIL Lamp on VIN: 2GCEK19R1T
P0171: Fuel Trim System Lean (Bank 1). this truck came to my shop because when you give it gas it does not rev up it stumbles and cuts out and sometimes dies the cam retard was at 20 degrees when it came in customer told me he replaced the engine and removed the distributor i removed the distributo...
May 14, 2010
2001 Nissan Pathfinder SE 3.5L Hesitation, Cuts out, Misfire VIN: JN8DR07Y81
P0171: Fuel Trim Lean (Bank 1). This one seems like a mass air flow sensor, but we cannot get it to check bad. Vehicle will bog down and not accelerate above 3000 rpm with no acceleration under load. Voltage side of MAF scoped well, but showed higher than we like on ground side (35 millivolt...
May 18, 2010
1996 Dodge Ram 1500 3.9L Excessive Emissions, Poor Idle Quality, Hesitation, Cuts out, Misfire, Poor Fuel Economy, MIL Lamp on, VIN: 1B7HC16X3T
P0171: Lean Bank 1. Hey everybody, I have a 96 ram 3.9 4X2 driving me crazy. This truck is running very lean. I am out of idea's, heres what i have done: Fuel press is 58 psi. with 12 oz in 20 sec for volume and no air bubbles, engine vacuum is 18 hg at idle and drops to zero whe...
May 20, 2010
2002 Ford F-150 XL 4.2L MIL Lamp on VIN: 1FTRF172X2
P0171: Engine lean bank 1. ... number of ford trucks, f150's ,rangers, different engines. customer has a code p0171, p0174, engine lean bank 1 bank 2. Fuel pressure is in spec, but filter changed anyway for good measure, fuel injection cleaned, unable to find any vaccum leaks, even repl...
May 24, 2010
2002 Chevrolet Impala 3.8L MIL Lamp on VIN: 2G1WH55K52
P0171: Fuel Trim System Lean. Vehicle came in with no power. Diagnosed plugged cat. Customer had cat replaced at muffler shop(aftermarket cat) vehicle came back 2 days later mil light on. Dtcs 171 1811. Scan data showed 02 sensors low mvs at idle in closed loop. Voltage at 43mv and not flu...
May 26, 2010