GM 19353734 Ignition Coil Assembly

To remove the ignition coil assembly, start by disconnecting the negative battery cable and removing the intake manifold service cover. Then, disconnect the electrical connector from the ignition control module and remove the radiator support cover, moving the radiator hose out of the way. Next, remove the ignition coil assembly bolts in the indicated sequence and take out the assembly from the valve cover. Inspect the spark plug boots for carbon tracking and deterioration. When installing the ignition coil assembly, tighten the mounting bolts gradually and evenly. For the rear ignition coil assembly, follow the same steps but also remove the Air Injection Reaction (AIR) vent solenoid. If replacing the ignition control module, tighten the mounting bolts in the indicated sequence. Finally, install the AIR vent solenoid and reverse the removal process for installation.

To remove and install the ignition coils and ignition control module assembly, first disconnect the battery's negative terminal. If needed, remove the cooling fan for access. Unplug the module's electrical connectors and label and detach the coil wires. Remove the assembly bolts and lift it out. Separate the coils from the ignition control module by removing their bolts. If removing the ignition system assembly, disconnect the IOI harness, remove assembly-to-camshaft bolts, lift it off, and detach the housing. Disconnect coil harnesses, remove coils, and then remove the ignition control module from the cover using screws. Reinstall in the reverse order.

To check the ignition coil, start by connecting one lead of an ohmmeter to the terminal of the ignition coil lead and the other lead to the ground. Flex the leads by hand to check for intermittent opens, and the ohmmeter should always indicate infinite resistance. If it doesn't, the ignition coil is defective and needs to be replaced. Next, connect the ohmmeter leads to both terminals of the ignition coil lead and flex the leads by hand again. The ohmmeter should read a steady value between 500 and 1,500 ohms as the leads are flexed. If it doesn't, the ignition coil is defective and should be replaced. To remove the ignition coil, start by detaching the cable from the negative terminal of the battery. Then, remove the distributor cap and rotor, and if necessary, remove the distributor itself. Remove the spring clip from the distributor shaft and mark the distributor tang drive and shaft for reassembly. Set the distributor in a vise with a shop rag to protect the shaft, and use a hammer and punch to remove the roll pin from the distributor shaft and gear. Lift the ignition coil assembly straight up and remove it from the distributor, noting the order in which the pieces were removed. Reassembly is the reverse of disassembly.

Start by removing the distributor cap and disconnecting the coil. Use an ohmmeter to check the resistance across the primary connections, ensuring it is close to zero. Then, test the resistance between the primary ground and the coil secondary connector, using both solid wire and dotted line connections. If the readings are infinite, the coil needs to be replaced.

If any of these tests fail, it indicates a faulty pick-up coil.

After lifting the ignition system assembly from the engine, detach the coil housing-to-cover screws and remove the housing from the cover.

If the ohmmeter does not indicate infinite resistance, it means the pick-up coil is defective and needs to be replaced.

The ohmmeter should not indicate an infinite resistance.

To check the High Energy Ignition System (HEI), start by disconnecting the battery's negative terminal. Use an ohmmeter to test the coil for opens and grounds. First, on the high scale, connect the ohmmeter leads; it should show a very high or infinite resistance value. Then, on the low scale, check the coil's primary resistance, which should indicate a very low or zero resistance value. Also, check the coil's secondary resistance on the high scale; it should not show an infinite resistance. If any values are off, replace the coil. For removal, unplug the coil's high tension wire and electrical leads, and remove the mounting nuts to take out the coil. The installation process is the reverse of removal.