LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Mercury >> 1981 >> Lynx LS, Automatic Trans >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> MCU Engine Control System >> Diagnosis & Testing >> Functional Test >> Engine Running Test (V8)
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Engine Running Test (V8)

  1. Check to see if engine has knock sensor. If so, have steel bar (socket extension) and tap hammer handy. Start engine and run at 2000 RPM for 2 minutes. Turn engine off, then immediately restart.
  2. Observe voltmeter for 4 initial pulses. As soon as pulses appear, hold steel bar against manifold near knock sensor and tap bar lightly with hammer for 15 seconds.
    NOTE: If more than 4 pulses appear, check for open circuit between coil and pin 8 of MCU module connector.
  3. Observe and record service codes. After 4 second pause, code(s) will be repeated. Stop engine and reconnect PCV valve. Refer to code chart to locate appropriate test.
scientia non olet · About LEMON Manuals