My engine check light came on and I had it checked with scanner and it shot out a code that read p0171 what do that mean and how do I take care of it

Asked by Dec 11, 2013 at 02:04 AM about the 1999 Ford Expedition

Question type: Maintenance & Repair

The engines check light does it cause the
interior light to come on to I drive a 99 ford
expedition 5.4 liter v8

1 Answer

251,235

code P0171 may mean that one or more of the following has happened: •The MAF (Mass Air Flow) Sensor is dirty or faulty Note: The use of "oiled" air filters may cause the MAF to become dirty if the filter is over-oiled. There is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry. •There could be a vacuum leak downstream of the MAF sensor •Possible cracked vacuum or PCV line/connection •Faulty or stuck open PCV valve •Failed or faulty oxygen sensor (bank 1, sensor 1) •Sticking/plugged or failed fuel injector •Low fuel pressure (possible plugged/dirty fuel filter!) •Exhaust leak between engine and first oxygen sensor

Your Answer

Ford Expedition Experts

  • #1
    T_S_T
    Reputation
    1,920
  • #2
    Larry Sturgis
    Reputation
    1,410
  • #3
    lightGear
    Reputation
    1,030
View All

Related Models For Sale

Used Chevrolet Tahoe
643 Great Deals out of 36,956 listings starting at $1,800
Used Ford Explorer
798 Great Deals out of 63,365 listings starting at $1,495
Used Chevrolet Suburban
293 Great Deals out of 20,596 listings starting at $1,000
Used Lincoln Navigator
96 Great Deals out of 5,080 listings starting at $1,900
Used Ford F-150
2,235 Great Deals out of 183,025 listings starting at $1,500
Used GMC Yukon
418 Great Deals out of 21,028 listings starting at $1,495
Used GMC Yukon XL
223 Great Deals out of 13,171 listings starting at $1,495
Used Cadillac Escalade
212 Great Deals out of 11,073 listings starting at $2,888
Used Dodge Durango
278 Great Deals out of 20,488 listings starting at $999
Used Ford Excursion
8 Great Deals out of 784 listings starting at $2,750
Used Toyota 4Runner
244 Great Deals out of 21,761 listings starting at $1,500
Used Ford F-250 Super Duty
357 Great Deals out of 43,715 listings starting at $1,250

Used Cars For Sale

2018 Ford Expedition For Sale
13 listings starting at $50,265
2017 Ford Expedition For Sale
25 Great Deals out of 12,614 listings starting at $28,993
2016 Ford Expedition For Sale
96 Great Deals out of 1,566 listings starting at $24,900
2015 Ford Expedition For Sale
12 Great Deals out of 568 listings starting at $19,995
2014 Ford Expedition For Sale
46 Great Deals out of 774 listings starting at $14,995

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.