Knock Sensor Test

1987 Jeep Wagoneer Base, 2.5 H, AutomaticSECTION Knock Sensor Test
  1. Start engine until engine reaches normal operating temperature. Connect Diagnostic Tester (M.S. 1700). Observe knock value on tester. Using tip of screw driver, gently tap on cylinder block next to knock sensor and observe knock sensor value on tester.
  2. Knock sensor value should increase while tapping on cylinder block. If knock sensor value does not increase while tapping on cylinder block, check knock sensor for proper connection. If connection is good, replace knock sensor.
RENDER: 1.0x

NO RELATED

Recommended Tools & Savings

Use the Manual With the Right Hardware

Pair factory procedures with proven DIY tools so the instructions are easier to execute.

Affiliate disclosure: We may earn a commission at no extra cost to you.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • β€’ You smell fuel, burning insulation, or see smoke.
  • β€’ Brakes feel soft, pull hard to one side, or make grinding noises.
  • β€’ The engine overheats, stalls repeatedly, or misfires under load.
  • β€’ You are missing required tools, torque specs, or safe lifting equipment.
  • β€’ You are not confident in the next step or safety outcome.