Diagnostic Method
Compare the diagnostic value with the threshold value, and if a condition meeting the criteria continues for the specified period of time or more, judge that there is a fault in the fuel system.
- After the engine is warmed up, when the air/fuel ratio feedback has stabilized, the fuel correction becomes extremely rich. (P0171)
- After the engine is warmed up, when the air/fuel ratio feedback has stabilized, the fuel correction becomes extremely lean. (P0172)
- Abnormal, when DTC for a rich status or a lean status is recorded, and the fuel correction amount during port injection is out of the specified value range. (P1170)
- Abnormal, when DTC for a rich status or a lean status is recorded, and the fuel correction amount during cylinder injection is out of the specified value range. (P117B)
JUDGMENT VALUE SPECIFICATION
| Malfunction Criteria | Threshold Value | DTC |
|---|---|---|
| Diagnostic value {[Short term fuel trim B1] + [Long term fuel trim B1] + ([A/F Sensor #1] -[Target Equivalence Ratio]) x 100} |
1.35 or more | P0171 |
| Less than value of Map | P0172 | |
| When port injection ratio is 100% 1.35 or more Or, Less than value of Map |
P1170 | |
| When cylinder injection ratio is 100% 1.35 or more Or, Less than value of Map |
P117B |
VALUE SPECIFICATION - MAP
| Warm-up increase compensation coefficient | 0 | 0.1 | 0.2 | 0.3 | 0.4 | 0.42 |
|---|---|---|---|---|---|---|
| Threshold Value | 0.65 | 0.56 | 0.49 | 0.42 | 0.36 | 0.35 |
Time needed for diagnosis:
P0171: 10s x 3time(s)
P0172: 10s x 3time(s)
P1170: 9s
P117B: 9s
Illumination of malfunction indicator light:
Illuminates when two consecutive driving cycles with fault occur. (P0171, P0172)
Malfunction indicator light does not illuminate even when malfunction occurs. (P1170, P117B)