Engine Controls - Basic Diagnostic Procedures: Diagnosis Suzuki Vitara I

VISUAL INSPECTION

Visually inspect following component condition and operation

1. Electrical wiring, looking for chafed, stretched, cut or pinched wires. Ensure electrical connectors fit tightly and are not corroded. See ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS article in ELECTRICAL.
2. Ensure vacuum hoses are properly routed and are not pinched or cut. See appropriate diagram in VACUUM DIAGRAMS article to verify routing and connections (if necessary).
3. Air filter element clogging.
4. Automatic transmission fluid condition, level and leakage.
5. Auxiliary engine components for looseness and installation.
6. Battery volage level, corrosion and terminal tightness.
7. Drive belt tension and condition.
8. Engine oil condition, level and leakage.
9. Engine coolant condition, level and leakage.
10. Engine oil pressure warning light operation.
11. Engine temperature gauge operation.
12. Exhaust system for leaks.
13. Fuel level and leakage.
14. Fuel level gauge operation.
15. Fuses blown.
16. Inspect air induction system for vacuum leaks.
17. MIL operation.
18. Tachometer operation (if equipped).
19. Throttle cable play and chaffing.

ENGINE BASIC INSPECTION

Note. Engine basic inspection is important for troubleshooting when no DTCs or other malfunction was found during visual inspection.

1. If engine system check has been performed, go to next step. If engine system check has not been performed, go to A4: ENGINE SYSTEM CHECK under SYSTEM TESTS in appropriate SELF DIAGNOSTICS article.
2. Check battery voltage. If battery voltage is 11 volts or more, go to next step. If battery voltage is not as specified, charge or replace battery.
3. Attempt to start engine. If starter cranks, go to next step. If starter does not crank, repair as necessary. See appropriate STARTERS article in STARTING & CHARGING SYSTEMS.
4. If engine starts, go to next step. If engine does not start, go to step 7.
5. Start engine and allow it to reach normal operating temperature. Ensure transmission is in Park (A/T) or Neutral (M/T), and all electrical loads are off (i.e., A/C, defogger or radio). Using Suzuki scan tool, select DATA LIST mode and observe IDLE SPEED parameter. If idle speed is 700-800 RPM, go to next step. If idle speed is not as specified, check Malfunction Indicator Light (MIL). See MALFUNCTION INDICATOR LIGHT INOPERATIVE under SYSTEM TESTS in appropriate SELF DIAGNOSTICS article.
6. Check ignition timing. See «IGNITION TIMING»(/suzuki/vitara/i-1988-2006/remont/adjustments/#engine-controls-on-vehicle-adjustments__ignition-timing) in ON-VEHICLE ADJUSTMENTS article.
7. Verify fuel tank contains a sufficient fuel supply. Pinch fuel return hose while turning ignition switch on and off. If fuel pressure pulses are felt as ignition is turned on and off, go to step 9. If fuel pressure pulses are not felt as ignition is turned on and off, go to next step.
8. Remove fuel filler cap. Listen for fuel pump sounds for 3 seconds after ignition is turned on. If fuel pump sounds are heard, check fuel pressure. See «FUEL PRESSURE»(ref-158706-S42048808762003101500000) under FUEL SYSTEMS in SYSTEM & COMPONENT TESTING article. If fuel pump sounds are not heard, go to «B-3: FUEL PUMP CIRCUIT INSPECTION»(ref-157312-S14054230572003080800000) under CIRCUIT TESTS.
9. Disconnect fuel injector 2-pin harness connectors. Perform spark test. See «SPARK TEST»(ref-157312-S11017747392003080800000) under IGNITION CHECKS. If strong Blue spark is observed, go to next step. If strong Blue spark is not observed, check ignition system. See «IGNITION SYSTEM»(ref-158706-S15598290812003101500000) in SYSTEM & COMPONENT TESTING article.
10. Install spark plugs and ignition coils. Using a mechanic's stethoscope, check each fuel injector for operating "clicking" sound as engine is cranked. (Scheme 1) If all fuel injectors made operating sound, check Malfunction Indicator Light (MIL). See MALFUNCTION INDICATOR LIGHT INOPERATIVE under SYSTEM TESTS in appropriate SELF DIAGNOSTICS article. If any one or all fuel injectors do not make operating sound, go to «B-2: FUEL INJECTOR CIRCUIT INSPECTION»(ref-157312-S11389353252003080800000) under CIRCUIT TESTS.

Scheme 1

Fuel Pressure Test

1. Release fuel system pressure. See «RELIEVING FUEL PRESSURE»(ref-157312-S01992232052003080800000). Remove fuel delivery feed hose from fuel delivery pipe (plug for Vitara). Install fuel pressure gauge between fuel delivery feed hose and fuel delivery pipe (plug for Vitara). (Scheme 2)
2. Verify battery voltage is 11 volts or greater. Turn ignition switch to ON position to operate fuel pump for 3 seconds. Turn ignition switch to OFF position. Repeat 3-4 times, and check fuel pressure. See «FUEL PUMP PERFORMANCE»(ref-157312-S18515564292003080800000) table. Start engine and allow it to reach normal operating temperature. Measure fuel pressure at idle. See «REGULATED FUEL PRESSURE»(ref-157312-S38358782132003080800000) table. Turn ignition switch to LOCK position.
3. If pressure is not within specification, check for faulty fuel pump, pressure regulator or restriction in fuel system. See «B-4: FUEL PRESSURE INSPECTION»(ref-157312-S34263555312003080800000) under CIRCUIT TESTS. Repair as necessary. Release fuel pressure, See «RELIEVING FUEL PRESSURE»(ref-157312-S01992232052003080800000). Remove fuel pressure gauge and reinstall fuel delivery feed hose (plug with new gasket for Vitara, tighten to 22 ft. lb.). Start engine. Ensure no fuel leaks are present.

Scheme 2

FUEL PUMP PERFORMANCE

REGULATED FUEL PRESSURE

B-4: FUEL PRESSURE INSPECTION

Note. Before performing fuel pressure inspection procedure, ensure battery is in good condition and fully charged.

See also:
• IDLE SPEED & MIXTURE
• IGNITION TIMING
• COMPUTER RELEARN PROCEDURES - SUZUKI
• ON-VEHICLE ADJUSTMENTS
• IDLE SPEED
• COLD (FAST) IDLE