1GR-FE ENGINE CONTROL SYSTEM – SFI SYSTEM
ES–319
ES
(i) Drive the vehicle at proper vehicle speed to perform fuel-cut operation (refer to the following HINT).
HINT:
Fuel-cut is performed when the following conditions are met:
•
Accelerator pedal fully released.
•
Engine speed is 2,500 rpm or more (fuel injection returns at 1,000 rpm).
(j) Accelerate the vehicle to 40 mph (64 km/h) or more by depressing the accelerator pedal for at least 10
seconds.
(k) Soon after performing step (j) above, release the accelerator pedal for at least 4 seconds without
depressing the brake pedal, in order to execute fuel-cut control.
(l) Allow the vehicle to decelerate until the vehicle speed declines to less than 6 mph (10 km/h).
(m) Repeat steps from (h) through (k) above at least 3 times in one driving cycle.
HINT:
Completion of all A/F sensor monitors is required to change the value in TEST RESULT.
CAUTION:
Strictly observe posted speed limits, traffic laws, and road conditions when performing these
drive patterns.
INSPECTION PROCEDURE
HINT:
Malfunctioning areas can be identified by performing the A/F CONTROL function provided in the ACTIVE
TEST. The A/F CONTROL function can help to determine whether the Air-Fuel Ratio (A/F) sensor, Heated
Oxygen (HO2) sensor and other potential trouble areas are malfunctioning.
The following instructions describe how to conduct the A/F CONTROL operation using an intelligent
tester.
(1) Connect an intelligent tester to the DLC3.
(2) Start the engine and turn the tester ON.
(3) Warm up the engine at an engine speed of 2,500 rpm for approximately 90 seconds.
(4) Select the following menu items: DIAGNOSIS / ENHANCED OBD II / ACTIVE TEST / A/F CONTROL.
(5) Perform the A/F CONTROL operation with the engine in an idling condition (press the RIGHT or LEFT
button to change the fuel injection volume).
(6) Monitor the voltage outputs of the A/F and HO2 sensors (AFS B1S1 and O2S B1S2 or AFS B2S1 and
O2S B2S2) displayed on the tester.
HINT:
•
The A/F CONTROL operation lowers the fuel injection volume by 12.5 % or increases the injection
volume by 25 %.
•
Each sensor reacts in accordance with increases and decreases in the fuel injection volume.
Standard
NOTICE:
The Air-Fuel Ratio (A/F) sensor has an output delay of a few seconds and the Heated Oxygen
(HO2) sensor has a maximum output delay of approximately 20 seconds.
Tester Display
(Sensor)
Injection Volumes
Status
Voltages
AFS B1S1 or AFS B2S1
(A/F)
+25 %
Rich
Less than 3.0
AFS B1S1 or AFS B2S1
(A/F)
-12.5 %
Lean
More than 3.35
O2S B1S2 or O2S B2S2
(HO2)
+25 %
Rich
More than 0.55
O2S B1S2 or O2S B2S2
(HO2)
-12.5 %
Lean
Less than 0.4