LEMON Manuals: Even more car manuals for everyone
Home >> Subaru >> 2015 >> WRX STI >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> Diagnostic Trouble Code (DTC) Detecting Criteria (H4DOTC) (STI) >> Diagnostic Trouble Code (DTC) Detecting Criteria >> DTC P0171 System Too Lean (Bank 1) >> Diagnostic Method

Diagnostic Method

Compare the diagnostic value (fsobd) with the threshold value, and if a condition meeting the malfunction criteria below continues for 10 s x 3 time(s) or more, judge that there is a fault in the fuel system.

Judgment Value 

JUDGMENT VALUE SPECIFICATION

Malfunction Criteria Threshold Value
fsobd = (sglmd - tglmda) + faf + flaf ≥ Value from Map
In this case: sglmd = measured lambda
tglmda = target lambda
faf = main feedback compensation coefficient (every 64 milliseconds)
flaf = main feedback learning compensation coefficient
 

Map 

AMOUNT OF AIR SPECIFICATION - MAP

Amount of air (g (oz)/s) 0 (0) 2.34375
(0.08)
4.6875
(0.17)
7.03125
(0.25)
9.375
(0.33)
11.71875
(0.41)
14.0625
(0.5)
fsobdL1 (%) 1.35 1.35 1.35 1.35 1.35 1.35 1.35

Time Needed for Diagnosis:  10 s x 3 time(s)

Malfunction Indicator Light Illumination:  Illuminates when malfunction occurs in 2 continuous driving cycles.