2015 Forester P0171 finally got to use the advanced functionality of my fancy scan tool

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I bought a used scan tool, a fancy one that does a lot of stuff like give you live data and other good stuff :cool:

This is the first time I needed to scan the CEL after buying it.

The P0171 came up twice: one is stored, the other is permanent

Here is the data:
P0171 (1/2) Stored

Fuel Sys 1 -- CL
Fuel Sys 2 -- N/A
Calc Load -- 9.0%
ECT -- 144 F
STFT B1 -- 34.4%
LTFT B1 -- 3.1%
MAP -- 9 in Hg
Eng RPM -- 679
Veh Speed - 0 mph
Spark Adv - 19.0 deg
IAT -- 21 F
MAF -- 0.22 lb/min
TPS -- 12.2%
O2SLoc -- O2S11, O2S12
O2S B1S2 -- 0.130V
STFT B1S2 -- 0.0%
OBDSup -- OBD and OBD II
Run Time -- 380 sec
Command EGR -- 0.0%
EGR Error -- 0.0%
Fuel Level -- 99.6%
BARO -- 30 in Hg
ECU Volts -- 14.404 V
LOAD Value -- 10.2%
EQ Ratio -- 0.991
Rel TPS -- 0.8%
Ambient -- 16 F
TPS B -- 29.4%
ACC Pedal D -- 13.7%
ACC Pedal E -- 14.1%
Command TAC -- 0.0%
N/D_STAT -- NEUT
GEAR_RCMD -- Neutral

P0171 (2/2) Permanent

This car seems to only have one upstream oxygen sensor (usually there is one for each bank) :unsure:
 
The oxygen sensors B1S1 & B1S2 is right next to each other. It is hard to see but it is on the passenger side front corner of the engine.

You got a big vacuum leak somewhere, either external or internal.
 
The oxygen sensors B1S1 & B1S2 is right next to each other. It is hard to see but it is on the passenger side front corner of the engine.

You got a big vacuum leak somewhere, either external or internal.

If it makes a difference, there is no driveability problems at all. Don't vacuum leaks usually cause idle issues?

Do those smoke machines actually work?
 
The oxygen sensors B1S1 & B1S2 is right next to each other. It is hard to see but it is on the passenger side front corner of the engine.

You got a big vacuum leak somewhere, either external or internal.
I was thinking the same. You are in 16F weather, the coolant is at 144F, 6 minutes after starting up. The STFT being in the 30's% is unusual (you are idling, given its 660-670 rpm.) So you didn't stick the gas pedal right prior to getting this freezeframe. If the STFT doesn't come down with the LTFT coming up, then the STFT is just swinging all over the place. This is one giveaway of an air leak. Your MAP is normal for idle at 9inHg (lots of vacuum). One possibility is an air leak at the exhaust, where fresh air can flow into the exhaust stream intermittently and hit the O2 sensor, making it think that it needs more proportion of fuel next instance. Just remember that your injectors are trying to match the expectant air for combustion. If it stays off, then at the very least your gas mileage will suffer. Note: I'm a 2014 Subaru Forester owner, and have had a bluetooth OBDLink hooked up and set up running live feed most of the time.
 
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