LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> GMC >> 1997 >> Forward Control 7.4 J >> Repair and Diagnosis >> External Pages >> Different car >> Section 46 (Engine Controls - Basic Testing - 5.7L) >> C-4, Basic Ignition System Checks >> HEI-Est Distributor >> Spark
April 5, 2026: LEMON Manuals is launched! Read the announcement.

HEI-Est Distributor: Spark

WARNING: This page does not describe the selected car, but rather 19 other vehicles, including the 1996 Chevrolet Chevy Van, 1995 GMC Yukon, 1995 GMC Vandura Special, 1995 GMC Vandura, and 1995 GMC Suburban. However, it is still accessible from the selected car via links, so may be relevant.
  1. If factory tachometer is connected to ignition coil tachometer terminal, disconnect it before performing tests. When removing spark plug wire from spark plug, twist and pull on boot. DO NOT  pull on wire.
  2. Using Spark Tester (ST-125), check for spark at coil wire (if applicable) and at each spark plug wire. Check spark plug wire resistance on suspect wires. Resistance should not be greater than 30,000 ohms.
scientia non olet · About LEMON Manuals