Engine Controls - Tests W/o Codes: Diagnosis Suzuki X-90 I

SYMPTOM DIAGNOSIS

Symptom checks cannot be used properly unless the problem occurs while the vehicle is being tested. To reduce diagnostic time, ensure steps in appropriate BASIC TESTING and TESTS W/CODES articles were performed before diagnosing a symptom.

1. For Esteem, see «BASIC TESTING»(ref-26202) and «TESTS W/CODES»(ref-26221) .
2. For Sidekick, see «BASIC TESTING - 1.6L»(ref-26203) and «TESTS W/CODES - 1.6L»(ref-26206) or «BASIC TESTING - 1.8L»(ref-26210) and «TESTS W/CODES - 1.8L»(ref-26212) .
3. For Swift, see «BASIC TESTING»(ref-26213) and «TESTS W/CODES»(ref-26214) .
4. For X-90, see «BASIC TESTING»(ref-26216) and «TESTS W/CODES»(ref-26219) .

Symptoms available for diagnosis include

1. Difficult Or No Start (Cranks Okay)
2. Engine Misfires Or Has Lack Of Power
3. Rough Or Unstable Idle
4. Engine Hesitates
5. Engine Surges
6. Spark Knock/Detonation
7. Poor Fuel Mileage
8. Fails Emission Test
9. Overheating

FAILS EMISSION TEST

1. Check for clogged air filter.
2. Check for abnormal engine operating temperature.
3. Check for fuel leakage from injectors.
4. Check for fuel pressure out of specification.
5. Check for faulty Engine Coolant Temperature (ECT) sensor.
6. Check for faulty Intake Air Temperature (IAT) sensor.
7. Check for faulty PCM.
8. Check for faulty EGR system.
9. Check for improper ignition timing.
10. Check for malfunctioning ignition system.
11. Check for lead contamination in catalytic converter.
12. Check for misrouted vacuum hoses.
13. Check for poor compression.
14. Check for vacuum leaks.

INTERMITTENT PROBLEM DIAGNOSIS

Intermittent fault testing requires duplicating circuit or component failure to identify the problem. These procedures may lead to the computer setting a trouble code which may help in diagnosis.

If problem vehicle does not produce trouble codes, monitor voltage or resistance values using a DVOM while attempting to reproduce conditions causing intermittent fault. A status change on DVOM indicates a fault has been located.

Use a DVOM to pinpoint faults. When monitoring voltage, ensure ignition switch is in ON position or engine is running. Ensure ignition switch is in OFF position or negative battery cable is disconnected when monitoring circuit resistance. Status changes on DVOM during test procedures indicate area of fault.