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P0171 Diagnostic Trouble Code Discussion for January 2015

Fuel System Lean (Bank 1)


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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2007 Honda Civic EX 1.8L Hesitation, Cuts out, Stall, MIL Lamp on VIN: 1HGFA16867
P0171: Fuel System Too Lean (Bank 1). ... power P0171 x3. Cleaned MAF, road tested 2x no problems.Following Monday car was back same problem. Replaced with known good MAF, cleared code, road tested- still no power mostly on hard acceleration but will get to 60 mph. P0171 in pending codes right awa...
January 02, 2015
1998 Ford F-150 Lariat 5.4L Excessive Emissions, Poor Idle Quality, Misfire, MIL Lamp on VIN: 1FTRX17L8W
P0171: bank 1 too lean. Ok, after reading the repair history, the customer came back, saying that truck was running worse. Scan data gave 4 codes. I had explained the last 2 times he was here that we needed to diag/repair the Fuel Pressure Sensor, because its reading a constant 5v. ...
January 06, 2015
2011 Ford Fiesta SE 1.6L MIL Lamp on VIN: 3FADP4BJ5B
P0171: Bank 1 lean. This vehicle came in with a p0171 Bank 1 lean. Found no vac. leaks. Vehicle has long term trims between 16 and 24 with short term being around -5 to 5. Any common issues with these?
January 08, 2015
2005 BMW X3 3.0i 3.0L MIL Lamp on VIN: WBXPA93435
P0171: lean bank 1. codes p0171, p0174 long term trim numbers run about 15 at idle in park, a little lower in gear. near 0 on road. smoke test showed leakage at runner control valve assy so I replaced that and cleared codes. smoke test better but trim is the same. crank venting s...
January 14, 2015
2007 GMC Sierra 1500 WT 5.3L Excessive Emissions, MIL Lamp on VIN: 2GTEK13M57
P0171: Fuel System Lean (Bank 1). MAF replaced with harness smoked intake-found no leaks come off idle fuel trims are great- idle engine long term go high short term are perfect. gotta have a vacuum leak somewhere!!! pulled upper intake manifold -found gaskets were deformed. problem still ther...
January 16, 2015
2000 Toyota Corolla VE 1.8L Hesitation, Cuts out, MIL Lamp on VIN: 1NXBR12E0Y
P0171: Fuel System Too Lean (Bank 1). thanks for help. at point of guessing. customer brought vehicle to us after unsuccessful tune up at pep boys they also replaced the maf there.. car actually ran worse after he got it. it had multiple codes for misfire (all but #2) and lean code. we checked plu...
January 19, 2015
1996 Nissan Altima GLE 2.4L Excessive Emissions, MIL Lamp on VIN: 1N4BU31D0T
P0171: Fuel Trim Lean (Bank 1). Need help on this one. No vacuum leaks found,fuel pressure is normal,replaced front o2 sensor,maf sensor and computer but no difference. After it gets hot, front o2 sensor reads o volts and pollutes lots of co. Rear o2 sensor reads 800mv while front one reads ...
January 20, 2015
2007 GMC Sierra 1500 WT 5.3L Excessive Emissions, MIL Lamp on VIN: 2GTEK13M57
P0171: Fuel Trim System Lean (Bank 1). MAF replaced with harness smoked intake-found no leaks come off idle fuel trims are great- idle engine long term go high short term are perfect. gotta have a vacuum leak somewhere!!! pulled upper intake manifold -found gaskets were deformed. problem still ther...
January 22, 2015
2002 Mercury Mountaineer 4.6L No Start, MIL Lamp on VIN: 4M2ZU86W62
P0171: Lean Bank One. Vehicle requires repeated cranking to start. Fuel pressure is slow to rise. Once running, it performs well in all conditions but throws codes for lean condition. I wanted to check for regulator or pressure sensor as Alldata suggests. I don't see either,believe...
January 25, 2015
1998 Ford Explorer Eddie Bauer 4.0L Poor Idle Quality VIN: 1FMZU34E6W
... with a classic upper intake gasket vacuum leak. P0171 & 174 that's not the issue. It also has a very dry rotted air intake tube; no rot holes yet but is not in good shape at all. Hate to ship it like that. The 1998 tube is discontinued; Dorman doesn'...
January 27, 2015
1998 GMC C1500 Sierra SL 4.3L MIL Lamp on VIN: 1GTEC14W0W
P0171: Fuel Trim System Lean (Bank 1). Hoping you guys and can help me out here, I'm at a loss. Sorry in advance for this being so long, but I wanted to be thorough. Truck originally came in with P0172,P0175 Both Banks Rich. Testing found FPR leaking, after replacement fuel pressure held but was 80...
January 27, 2015
2005 Volkswagen Passat GLS 1.8L Misfire, MIL Lamp on VIN: WVWDD63BX5
P0171: Bank 1 Too Lean. Clear codes and vehicle runs perfect. After driving under heavy load, vehicle will intermittently idle rough and misfire. Normal idle MAF reading is 3.5 g/s or so, when misfiring the MAF is reading between 7 and 10 g/s. Also when misfiring fuel trim will be ma...
January 28, 2015
1998 Ford Explorer Eddie Bauer 4.0L Poor Idle Quality VIN: 1FMZU34E6W
... with a classic upper intake gasket vacuum leak. P0171 & 174 that's not the issue. It also has a very dry rotted air intake tube; no rot holes yet but is not in good shape at all. Hate to ship it like that. The 1998 tube is discontinued; Dorman doesn'...
January 29, 2015
2009 Nissan Versa S 1.8L MIL Lamp on VIN: 3N1BC11E69
P0171: fuel system too lean b1. ... to me with a code P0171 which is preventing it from passing insp. The customer has replaced the front a/f sensor / all fuel injectors / map sensor / all sparl plugs and coils and gave up and asked me to take a look. i took fuel pressure good 51psi at idle ...
January 30, 2015
2004 Mercedes-Benz C230 Kompressor 1.8L Excessive Emissions VIN: WDBRN40J44
good morning guys. well, again I need your help. working on 04 mercedez c230 w/supercharge. customer has replace up and down oe o2 sensor, other shop found oil in Ecm , o2, and cam adjuster connector. they clean them good, and they scan for po172 which is rich...
January 31, 2015
2009 Nissan Versa S 1.8L MIL Lamp on VIN: 3N1BC11E69
P0171: fuel system too lean b1. ... to me with a code P0171 which is preventing it from passing insp. The customer has replaced the front a/f sensor / all fuel injectors / map sensor / all sparl plugs and coils and gave up and asked me to take a look. i took fuel pressure good 51psi at idle ...
January 31, 2015