Engine: Testing and Inspection
CO/HC
HINT: This check is used only to determine whether or not the idle CO/HC complies with specifications.
1. INITIAL CONDITIONS
a. Engine at normal operating temperature
b. Air cleaner installed
c. Air pipes and hoses of air induction system connected
d. All accessories switched OFF
e. All vacuum lines properly connected
g. SFI system wiring connectors fully plugged
g. Ignition timing check correctly
h. Transmission in neutral position
i. Tachometer and CO/HC meter calibrated by hand
2. START ENGINE
3. RACE ENGINE AT 2,500 RPM FOR APPROXIMATELY 180 SECONDS
4. INSERT CO/HC METER TESTING PROBE AT LEAST 40 cm (1.3 ft.) INTO TAILPIPE DURING IDLING
5. IMMEDIATELY CHECK CO/HC CONCENTRATION AT IDLE AND/OR 2,500 RPM
Complete the measuring within 3 minutes.
HINT: When performing the 2 mode (2,500 rpm and idle) test, follow the measurement order prescribed by the applicable local regulations.
If the CO/HC concentration does not conform to specifications, perform troubleshooting in the order given below.
1. Check the A/F sensor operation.
2. See the table for possible causes, and then inspect and correct the applicable causes if necessary.
COMPRESSION
HINT: If there is lack of power, excessive oil consumption or poor fuel economy, measure the compression pressure.
1. WARM UP AND STOP ENGINE
Allow the engine to warm up to normal operating temperature.
2. REMOVE IGNITION COILS
3. REMOVE SPARK PLUGS
4. INSPECT CYLINDER COMPRESSION PRESSURE
a. Insert a compression gauge into the spark plug hole.
b. Fully open the throttle.
c. While cranking the engine, measure the compression pressure.
HINT: Always use a fully charged battery to obtain engine speed of 250 rpm or more.
d. Repeat steps (a) through (c) for each cylinder.
NOTICE: This measurement must be done in as short a time as possible.
Compression pressure: 1.300 kPa (13.8 kgf/cm2, 196 psi)
Minimum pressure: 1.00 MPa (10 kgf/cm2, 142 psi)
Difference between each cylinder: 100 kPa (1.0 kgf/cm2, 14 psi)
e. If the cylinder compression in one more cylinders is low, pour a small amount of engine oil into the cylinder through the spark plug hole and repeat steps (a) through (c) for cylinders with low compression.
- If adding oil helps the compression, it is likely that the piston rings and/or cylinder bore are worn or damaged.
- If pressure stays low, a valve may be sticking or seating is improper, or there may be leakage through the gasket.
5. REINSTALL SPARK PLUGS
6. REINSTALL IGNITION COILS
IGNITION TIMING
1. WARM UP ENGINE
Allow the engine to warm up to normal operating temperature.
2. CHECK IDLE SPEED
3. CONNECT TIMING LIGHT
Connect the tester probe of a timing light to the black-white service wire of the engine wire as shown in the illustration.
4. INSPECT IGNITION TIMING
a. Using SST, connect terminals to TC and CG of the DLC3.
SST 09843-18040
HINT: After engine rpm is kept at 900 - 1,500 rpm for 5 seconds, check that it returns to idle speed.
b. Using a timing light, check the ignition timing.
Ignition timing: 8 to 12° BTDC @ idle
c. Remove the SST from the DLC3.
5. FURTHER CHECK IGNITION TIMING
Ignition timing: 5 to 15° BTDC @ idle
HINT: The timing mark moves in a range between 5 and 15°.
6. DISCONNECT TIMING LIGHT
IDLE SPEED
INSPECTION
1. INITIAL CONDITIONS
a. Engine at normal operating temperature
b. Air cleaner installed
c. All pipes and hoses of air induction system connected
d. All vacuum lines properly connected
e. SFI system wiring connectors fully plugged
f. All operating accessories switched OFF
g. Ignition timing check correctly
h. Transmission in neutral range
i. A/C switched OFF
2. CONNECT HAND-HELD TESTER OR OBD II SCAN TOOL
a. Connect the hand-held tester or OBD II scan tool to the DLC3.
b. Please refer to the hand-held tester or OBD II scan tool operator's for further details.
3. INSPECT IDLE SPEED
a. Race the engine at 2,500 rpm for approximately 90 seconds.
b. Check the idle speed.
Idle Speed (w/ Cooling Fan OFF):
If the idle speed is not as specified, check the air intake system.
4. DISCONNECT HAND-HELD TESTER OR OBD II SCAN TOOL