Engine Electrical
Ignition Control Unit
An ignition control unit, often called an ignition module, switches the ignition coil on and off to create spark. We list 31 ignition control units from $21 to $349 for vehicles from 1972-2008, from Standard Motor Products, AC Delco, Accel and Delphi, with fits for the Chevrolet Malibu and Corvette and the Ford Mustang.
Shop ignition control unit by vehicle
Delphi Ignition Control Unit W0133-1865924 for Chevrolet Malibu
Fits 2004–2006 models
What the module does
The ignition control unit reads a timing signal from a pickup in the distributor or a crankshaft sensor, then switches the coil to fire each spark plug at the right moment. On many GM engines the module sits inside the distributor. On some Ford engines it mounts on the side of the distributor or on the fender.
If the module fails, the engine loses spark.
Symptoms of failure
Common signs include a crank with no start and no spark, stalling once the engine is warm, intermittent cutting out, and misfires. Heat is the usual trigger, so a module that fails when hot may work again once it cools.
Test for spark when the problem happens, then check the pickup coil, the ignition coil and the wiring. Many parts stores and service guides list a module test procedure.
Choosing and fitting
Match engine size, year and ignition type. Listings show terminal count, connector shape and terminal type, such as 4 blade terminals, so compare them with your old module.
Disconnect the battery first. Clean the mounting surface and apply heat sink compound where the module mounts on metal, since modules rely on it to shed heat. Without it, a new module can overheat and fail early.
Ignition Control Unit questions
Can an ignition module fail only when hot?
Yes. Heat related failure is common. The engine may stall when hot and restart after cooling. Test for spark while the fault is present. A spark tester makes this check easy.
Do I need dielectric grease or heat sink compound for an ignition module?
Most modules need heat sink compound on the mounting base to carry heat away. Use what the instructions call for. Without the compound, a new module can overheat and fail early.
What is the difference between an ignition module and an ignition coil?
The module is the switch that tells the coil when to fire. The coil creates the high voltage for the spark plugs. Both are needed for spark.