Detonation Sensor Test
NOTE:
This test applies to 318" 4-barrel V8 engine only.
- Connect a variable timing light to engine. Start engine and run it on second highest step of fast idle cam (about 1200 RPM). Connect an auxiliary vacuum supply of 16 in. Hg vacuum.
- Tap lightly on the manifold near the sensor, using a small end wrench. Using the timing light, look for a decrease in spark advance. The amount of decrease in timing should be in proportion to the strength and frequency of the tapping. Maximum decrease in timing would be 11°. Shut off engine and disconnect timing light.