The ignition module of your vehicle is the heart of your entire ignition system. Its two main roles are to create a spark strong enough to ignite the air/fuel mixture for combustion and to control the timing of the spark plugs by opening and closing the ignition coil ground circuit. The ignition module has a direct impact on the performance of the engine.
The module resembles a small electrical box with a wire harness. It is usually located on or in the distributor housing in domestic vehicles, and on the firewall or wheel-well in foreign vehicles.
Like all automobile components, the ignition module will eventually deteriorate and break. However, you can anticipate and prepare for the failure. These tips will help you recognize the two most common symptoms of ignition module failure.
Overheating is a common indicator that you could be having an ignition module problem. Ignition modules that are overheating will soon completely cease to function and in the meantime can cause cause electrical shorts, engine stuttering, lower gas mileage, power loss, stalling, and gasoline odors in the exhaust.
You can test for overheating while the car still runs. Idle the engine for 30 minutes, and then tap the module with a screwdriver. The car may stall, which would strongly suggest that ignition control module may be the cause of the overheating you're experiencing.
If you are caught with an overheated module in an emergency situation, you can cool it down with ice water, engine coolant, or refrigerant fluid. However, this is a temporary solution only to be used as a last resort until you can reach repair facilities.
2. Sudden Failure
If your vehicle stalls unexpectedly during operation and will not start again, it is likely because of loose or corroded electrical connections in the ignition module. In this case, check the switch, clean oxidized terminals, and replace broken wires if necessary.
It’s also possible the circuits may be critically damaged by overheating if the problem is not addressed after the first or second occurrence. If you cannot start the car, you need to test the ignition control module using a light timing tester to check the output of the module.
Connect the timer to the positive terminal of the battery and check the continuity of the black output wire while cranking the starter. If the light blinks, the module is good. If the light is blank or constant, the module is bad. Before you attempt to replace the control module, you must rule out other ignition system components. The module is expensive and replacing it is a laborious process. Check the ignition coil for a spark. Examine the wires at the cap, rotor, and spark plugs. If the car runs but has timing problems, use a tester light and wrench to adjust the spark plug timing according to the manufacturer’s specifications.
Deteriorating Ignition Module FAQ
What kills an ignition module?
Heat is one of the main reasons an ignition module fails. As cars age, the distributor begins to wear out and this can cause a buildup of heat that can damage other parts of the car, such as the ignition module.
How long do ignition control modules last?
On average, ignition control modules should be replaced every 100,000 miles or so. However, modules may stop working sooner due to other mechanical issues or damage.
How can I test my ignition module?
The ignition module can be tested with the multimeter. The red lead should be placed on the positive ignition coil terminal, while the black should be attached to a metal part of the car.
It's very important to ground the black terminal to a part of metal on the car.
You should get a reading between 0.4 and 2 ohms when the car engine is engaged.
How do you reset an ignition control module?
You can reset your ignition control module in just a few minutes. First, locate the fuse box, which is often near the battery.
With the car turned off, remove the fuses and disconnect the car's battery. Wait about 10 minutes and then reconnect and battery and put the fuses back in position.
Turn the car on and let it idle for about 10 minutes. This should reset the ignition control module.
Do you need an ignition control module?
The ignition control module tells the ignition coil when to fire, which essentially means this is what starts the engine of the vehicle. With a working ignition control module your engine might misfire, stutter, and even lose power.
You'll also notice a reduced fuel economy with a faulty ignition control module. There is no way to bypass an ignition control module because it is such an essential element of the vehicle.
Your car absolutely needs an ignition control module you need to repair or replace this part once it starts to go bad.