Subaru IMPREZA GD 2007 Series Manual page 1870

asieps_tobira_IM_US.book 79 ページ ２０１２年１月１７日 火曜日 午後３時４８分
Diagnostic Trouble Code (DTC) Detecting Criteria
2. ENABLE CONDITION
Secondary Parameters
A/F main learning system
Engine coolant temperature
Engine load
Intake air change during 0.5 engine revs. ≤ 0.02 g (0.001 oz)/rev
Learning value of EVAP conc. during
purge
Cumulative time of canister purge after
engine start
Continuous period after canister purge
starting
Map 5
Engine speed
Idling
(rpm)
Measured value Non- 0.228
(g(oz)/rev) turbo (0.008)
3. GENERAL DRIVING CYCLE
Perform the diagnosis continuously at idling or at a constant speed after warming up the engine.
4. DIAGNOSTIC METHOD
Abnormality Judgment
Compare the diagnosed value (fsobd) with the threshold value, and if a condition where the malfunction cri-
teria are met continues for 50 seconds or more, judge that there is a fault in the fuel system.
Judgment Value
Malfunction Criteria
fsobd = (sglmd – tglmda) + faf + flaf
where,
sglmd = measured lambda
tglmda = target lambda
faf = Main feedback compensation coef-
ficient
(every 64 milliseconds)
flaf = main feedback learning compensa-
tion coefficient
Map 4 Threshold value of fuel system malfunction criteria
Amount of air (g (oz)/s)
fsobdR1 (%)
Time Needed for Diagnosis: 10 seconds × 5 times
Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in two continuous driving
cycles.
Normality Judgment
Judge as OK when the malfunction criteria below continues for 10 seconds.
Judgment Value
Malfunction Criteria
fsobd = (sglmd – tglmda) + faf + flaf
Enable Conditions
In operation
≥ 70°C (158°F)
≥ Value from Map 5
≤ 0.1
20 seconds or more
30 seconds or more
800 1,200 1,600 2,000
0.22 0.22 0.22
(0.0078) (0.0078) (0.0078)
Threshold Value
≤ fsobdR1
Refer to Map 4.
fsobdR1 = rich side
threshold value of
fsobd
2.4 4.7 7
0
(0.085) (0.166) (0.247)
–40 –40 –36.9 –32.0
Threshold Value
≥ –20%
GD(H4DOTC)-79
2,400 2,800 3,200
0.228 0.23 0.234
(0.008) (0.0081) (0.0083)
9.4 11.7 14.1
(0.332) (0.413) (0.497)
–27.0 –27.0 –27.0
GENERAL DESCRIPTION
3,600 4,000 4,400
0.242 0.250 0.250
(0.0085) (0.0088) (0.0088)