P0171 System Too Lean??
Username
Do you already have an account?
Forgot your password?
  • Log in or Sign up

    Welcome to SwedeSpeed
    You're currently browsing Swedespeed as a guest. Please sign up or sign in and take part in the conversation with other Volvo owners and enthusiasts. With more than 2 million posts our community is one of the most active groups of Volvo owners in the world. Take a moment to sign up and enjoy all of the features our forums have to offer.
    Results 1 to 11 of 11
    1. #1
      Junior Member ewizzle's Avatar
      Join Date
      Oct 2006
      Location
      Seattle
      Posts
      384

      Question P0171 System Too Lean??

      So I just got back from the Gorge (150 miles from Seattle) this weekend from watching a weekend of DMB. So along the way there I got a Check Engine light came on and what it was is a P0171 - System Too Lean error code.

      The car is due for a 60k service and is sitting at 58,200 miles. Has any has this issue before?



    2. #2
      Google search with some good advice on where to start.

      Basically this means that an oxygen sensor in bank 1 detected a lean condition (too much oxygen in the exhaust). On V6/V8/V10 engines, Bank 1 is the side of the engine that has cylinder #1.
      Note: This DTC is very similar to P0174, and in fact your vehicle may show both codes at the same time.
      Symptoms

      You will more than likely not notice any drivability problems, although there may be symptoms such as a lack of power, detonation (spark knock), and/or a hesitation/surge on acceleration.
      Causes

      A 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 Solutions

      Possible solutions include:
      • In the vast majority of cases, simply cleaning the MAF sensor does the trick. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
      • Inspect all vacuum and PCV hoses, replace if necessary
      • Check for a dirty fuel filter and proper fuel pressure
      2009 V50 T5 AWD GT: Work in progress: (1) (2) (3) (4) (5)
      Previous rides: (1) (2)

    3. #3
      Global Moderator tmtalpey's Avatar
      Join Date
      Jun 2004
      Location
      Eastern MA
      Posts
      6,666
      Check for air leaks, especially ones at the exhaust flange.
      2005 V50 T5 AWD 6MT w/Heico tune, Heico exhaust, Bell intercooler, IPD TCV, Viva CBV, Elevate rear swaybar, Snabb shift kit, etc.
      2004 XC90 2.5T AWD
      1956 PV444 complete, running
      1956 PV444 very original, very rough

    4. #4
      First thing I look for is a vacuum leak, #1 cause is the hose that connects underneath the intake manifold (left side when facing the engine). Will also cause boost issues due to being a reference source for the TCV. Next make sure the upper PCV hose isnt cracked, very common if you havent had the repair done yet under extended warranty.

      Possible bad MAF or HO2S but less common than a simple vacuum leak.
      TheRetrofitSource | 2020 Motorsports | RTernie | H&R Springs | Import Meet | Girodisc

      Current: E46M (daily) | S40 T5 (grocery getter)
      Past: NA1 NSX | Acura TL | LS-T DC4

    5. #5
      Eric has a 2.4i so we can rule out the TCV or anything that's turbo specific.
      2005 S60R Ti Grey/Gobi/6M/18"Black Pegs
      1997 854R Black/Charcoal/Really Dark Bronze Volans/5M/ARD M4.4 BLUE/Daily Driver
      2005 S40 T5 FWD="http://www.cardomain.com/ride/2938966" SOLD/MISSED

    6. #6
      In that case check the upper PCV hose and possible MAF adaption out of range and needs ECM SW
      TheRetrofitSource | 2020 Motorsports | RTernie | H&R Springs | Import Meet | Girodisc

      Current: E46M (daily) | S40 T5 (grocery getter)
      Past: NA1 NSX | Acura TL | LS-T DC4

    7. #7
      Yet again, Another "Kyle FTW" post.
      2005 S60R Ti Grey/Gobi/6M/18"Black Pegs
      1997 854R Black/Charcoal/Really Dark Bronze Volans/5M/ARD M4.4 BLUE/Daily Driver
      2005 S40 T5 FWD="http://www.cardomain.com/ride/2938966" SOLD/MISSED

    8. #8
      Junior Member ewizzle's Avatar
      Join Date
      Oct 2006
      Location
      Seattle
      Posts
      384
      Hey guys, thanks for all the advice. It looks like there is exess presure build up in the oil. It was also making like a dying turkey noise and once the dip stick was pulled out, the car is fine. I guess there is another part behind the oil filter that must be dirty that is causing exess presure build up. Car is going in for a 60k fix up on monday anyway.

    9. #9
      PCV extended warranty, go!
      TheRetrofitSource | 2020 Motorsports | RTernie | H&R Springs | Import Meet | Girodisc

      Current: E46M (daily) | S40 T5 (grocery getter)
      Past: NA1 NSX | Acura TL | LS-T DC4

    10. #10
      Junior Member ewizzle's Avatar
      Join Date
      Oct 2006
      Location
      Seattle
      Posts
      384
      Quote Originally Posted by ForceFed Motorsports View Post
      In that case check the upper PCV hose and possible MAF adaption out of range and needs ECM SW
      Bingo - right on.

      25793 REPLACE PCV OIL TRAP & VENTILATION HOSE
      58466 PERFORMED SCAN TEST FOR DIAGNOSTIC TROUBLE CODES.. FOUND CODES FOR FUEL TRIM... CAUSED BY BROKEN HOSE AND FAILED OILFILTER HOUSING.. R & R HOSE AND HOUSING.. REPLACED PVC OIL TRAP AND VENTILATION HOSE AS PER R205..
      ewizzle

      2005 Volvo S40 2.4i

    11. #11
      Junior Member
      Join Date
      Sep 2009
      Location
      Pennsylvania
      Posts
      31
      I had my oil trap replaced under extended warranty yesterday. No charge. It was making the sound and release pressure when pulling out the dipstick. I had a 171 code show up a week or so ago. My 2006 V50 2.4i has 55k miles. Must say the dealer treated me great...even washed the car.
      Last edited by jbswedespeedv50; 09-14-2010 at 06:49 AM.