Description
The ECM controls the engine idle speed to a specified level through the fine adjustment of the air, which is let into the intake manifold, by operating the electric throttle control actuator. The operating of the throttle valve is varied to allow for optimum control of the engine idling speed. The crankshaft position sensor (POS) detects the actual engine speed and sends a signal to the ECM.
The ECM controls the electric throttle control actuator so that the engine speed coincides with the target value memorized in the ECM. The target engine speed is the lowest speed at which the engine can operate steadily.
The optimum value stored in the ECM is determined by taking into consideration various engine conditions, such as during warming up, deceleration, and engine load (air conditioner, power steering and cooling fan operation, etc.).
DTC Description
DTC DETECTION LOGIC
DTC No. | CONSULT screen terms (Trouble diagnosis content) | DTC detecting condition |
P050 | ISC SYSTEM (Idle air control system RPM lower than expected) | The idle speed is less than the target idle speed by 100 rpm or more. |
POSSIBLE CAUSE
FAIL-SAFE
Not applicable
DTC CONFIRMATION PROCEDURE
1.CHECK DTC PRIORITY
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
Is applicable DTC detected? YES >> Perform diagnosis of applicable. Refer to EC-93, "DTC Index".
NO >> GO TO 2.
2.PRECONDITIONING
If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
If the target idle speed is out of the specified value, perform EC-141, "Work Procedure", before conducting DTC Confirmation Procedure.
TESTING CONDITION:
>> GO TO 3.
3.PERFORM DTC CONFIRMATION PROCEDURE
Is 1st trip DTC detected? YES >> Proceed to EC-353, "Diagnosis Procedure".
NO >> INSPECTION END
Diagnosis Procedure
1.CHECK DTC PRIORITY
If DTC P0506 is displayed with other DTC, first perform the trouble diagnosis for other DTC.
Is applicable DTC detected? YES >> Perform diagnosis of applicable. Refer to EC-93, "DTC Index".
NO >> GO TO 2.
2.CHECK INTAKE AIR LEAK
Is intake air leak detected? YES >> Discover air leak location and repair.
NO >> Replace ECM. Refer to EC-499, "Removal and Installation".
P0520 EOP sensor
DTC Description
DTC DETECTION LOGIC
DTC No.
CONSULT screen terms
(Trouble diagnosis content)
DTC detecting condition
P0520
EOP SENSOR/SWITCH
(Engine oil pressure sensor/switch circuit)
Signal voltage from the EOP sensor remains at more than 5.02 V /
less than
...
Fuel pressure
Work Procedure
FUEL PRESSURE RELEASE
1.FUEL PRESSURE RELEASE
With CONSULT
Turn ignition switch ON.
Perform “FUEL PRESSURE RELEASE” in “WORK SUPPORT” mode of “ENGINE”
using CONSULT.
Start engine.
After engine stalls, crank it two or three times to ...
Specifications
Engine
Model
QR25DE
Type
Gasoline, 4-cycle, DOHC
Cylinder arrangement
4-cylinder
Bore x Stroke
in (mm)
3.5 x 3.9 (89.0 x 100.0)
Displacement
cu in (cm3)
151.82 (2,488)
Firing order
1-3-4-2
Idle speed
No ...