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P0171 Diagnostic Trouble Code Discussion for February 2021

Fuel System Lean (Bank 1)

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Trouble Ticket Help Requests for DTC P0171
Help Request Posted
2006 Honda Odyssey Touring 3.5L MIL Lamp on VIN: 5FNRL38826
P0171: Fuel System Too Lean (Bank 1). van came in with check engine light on and no drivability issues. Scanned data 02 sensor upstream current -.01 .00. ma map sensor .84 at idle. short fuel trim 1.17 to 1.12 3000 RMP both bank Long trim 1.17 Bank1 1.12 Bank 2 1.12 idle short trim bank 1 1.17...
February 03, 2021
2015 Buick Encore Premium 1.4L Poor Idle Quality, Stall, Hard start VIN: KL4CJHSB6F
P0171: System lean Bank 1. I have hit a mental block. I am lost as to what and how to test further. Fuel supply and injection are fine. Ignition is fine. There were no previous symptoms as to idle or performance before the concern began. It will run and idle well after several very ...
February 07, 2021
2012 Subaru Outback 2.5i 2.5L MIL Lamp on VIN: 4S4BRBAC8C
P0171: Lean bank 1. Came in with po301-302-303-304 and p0171, replaced worn plugs with 4 new coils gave back to customer 50 miles later check engine light returned with p0171, found air fuel learning 1 at 30 smoke tested found no leaks, replaced front o2 with napa part, no ch...
February 14, 2021
2013 Cadillac ATS 2.0L MIL Lamp on VIN: 1G6AG5RX4D
P0171: Lean bank 1. Vehicle was running bad, hesitated, put out black smoke. Checked out and had high fuel trims (40 LT and 18-20 for ST) Smoke tested with no signs of a leak, unhooked MAF sensor and readings zeroed out. Per tests we replaced the MAF sensor with an AC Delco a...
February 19, 2021
2008 Toyota Corolla S 1.8L MIL Lamp on VIN: 2T1BR32E88
P0171: Lean bank 1. Another P0171 which should be an easy diagnosis but is running us around in circles. The LT trim climbs at idle, the AFS runs between 3.2 and 3.4 volts. Downstream O2 runs a solid .66 volts. Checked for vacuum leads and could not find any. Checked MAF with...
February 23, 2021