CITRUS HEIGHTS (916) 726-8473

ROSEVILLE (916) 789-0303

LINCOLN (916) 645-2860

Duncan's Automotive

Diagnostics Driveability & Performance

We offer three levels of driveability/performance tests to track down even the most elusive performance problems.

Level 1

Visually inspect:

  • Battery cables and connections
  • Spark plug wires and secondary ignition components
  • Vacuum hoses and routing
  • Air inlet ducting
  • Wiring to sensors and actuators

Road test vehicle to verify symptoms

Check coolant level & engine operating temperature

Check system charging voltage and electrical system noise

Check idle speed

Check base ignition timing, dwell, and operation of timing advance controls

Check engine vacuum: cranking, idle & 2500 rpm

Analyze primary & secondary ignition signals on oscilloscope

Perform cylinder power balance test

Check fuel pressure

Check tail pipe emissions readings

Check for vacuum leaks

Pull and record Diagnostic Trouble Codes (DTCs)

Check for related technical service bulletins or IdentaFix® bulletins

Analyze data and recommend necessary repairs

Level 2

Perform additional, symptom specific diagnostics

Diagnose relevant DTCs

Lab scope analysis of sensors and actuators

Additional road testing as needed for dynamic tests of engine control systems and intermittent problems

Access diagnostic hot line and on-line sources

If cold start or warm up problem exists, vehicle will be needed for a minimum of two days.

Tests of warm engine parameters will be checked the first day and specific cold running systems will be checked the following day.

Level 3

Level 3 diagnostics are geared toward problems that are very intermittent and require extensive time to duplicate. Due to the nature of Level 3 diagnostics, appropriate tests are selected based on the nature of the symptoms and the results of earlier diagnostic tests.

Level 3 includes time for set up and road testing of vehicle with specialized equipment as needed and also includes time for an additional technician's time to monitor equipment during road tests for safe operation of the vehicle.