Classic Car Won’t Start: Troubleshooting Ignition Problems

A car that stutters when you turn the key can be one of the worst sounds to hear as a vintage car owner. Hearing no sound at all is just as bad. Whether your car is parked in your garage or you are out on a drive or at a show, you need your car to start dependably.

There are several reasons that a vintage car will not start, but there are diagnostic steps you can take on your own, many that require limited or no equipment, to determine the issue with your antique vehicle. From there, you can make the repairs to get your vehicle starting properly once more.

How the Ignition System Works

In a key start vintage car, turning the key sends a signal from the ignition coil to the solenoid relay. This signal connects the battery to the starter motor, providing the power necessary to turn the engine over. Simultaneously, fuel is injected into the engine. The spark plugs generate a spark that ignites the fuel in each of the cylinders and produces the power to run the car.

With so many separate parts, there are a variety of things that can go wrong. The underlying reason for this system failing is often the battery, the ignition, the fuel system, or mechanical failure of any of the parts, cables, or wires that transmit power from the ignition to the engine.

Diagnosing and Fixing an Antique Car that Does Not Start

A visual inspection under the hood is the best place to start. You want to look over wires and cables for any signs of corrosion or any loose connectors. Inspect each of your fuses as well for a blown or worn fuse. These are some of the most common issues behind a non-starting car, and are quick fixes since tightening a wire or replacing a fuse is fast.

If the initial visual inspection does not reveal any problems, it can still guide your troubleshooting and help you rule out causes. The next step is to use what you see and try some additional steps based on whether or not the starter cranks.

If the Starter Doesn’t Crank:

Called “no crank no start” by mechanics, this occurs when you turn the key and are met with silence. The most common cause is a dead battery. Many vintage car owners run their cars infrequently, and dead batteries are a common problem. The fix here is simply a jump. If your antique car has an older 6 volt system, it is important to remember that you cannot get the jump from a 12 volt car.

If you have confirmed that the battery is supplying power, but there is still no cranking, the next step is to:

• Check the Starter Solenoid - Cars made after the 1940s and before the 1970s typically have a separate starter solenoid that uses heavy gauge wires to relay power from the ignition to the motor. You should check the connections on the wires, look for any signs of corrosion, and make sure there is voltage traveling through all connecting wires.
• Clean the Battery Terminals - The terminals where wiring connects to your battery can get dirty through regular use of your car, and the dirt impedes the connection, and transfer of current, between them. Cleaning your battery terminals provides you a better connection without any loss of voltage.

Solving a “no crank no start” problem is often simpler than a car that is cranking but not starting or stalling shortly after starting. One of these two solutions will often fix the problem.

If the Starter Cranks:

Mechanics call this a “crank no start” case. When this happens, you can usually assume that the starter is working and the problem lies somewhere else in the system. To find out where:

• Test the Battery - The battery may still produce power, but be dying. An old battery cannot transmit enough power to turn the engine over or will crank too slowly to start the car. You can listen for a slow cranking or test the voltage of the current from the battery. If the voltage is less than 12 volts (or 6 volts depending on your car), it might be time to replace the battery.
• Check Spark Plugs - Spark plugs are common elements to go out. You can find out if yours are working by watching for a spark to jump from the spark plug to the cylinder while a friend cranks the engine. The easiest way to do this is with a spark tester which will also give you the strength of the spark so you can be sure it is strong enough. You can also do it without a spark tester by simply watching the spark.
• Make Sure Fuel Is Going into the Engine - When you crank the engine, fuel will pump into the carburetor. You will need to open the air filter box and carburetor to see inside, then have a friend turn the key. If you do not see fuel, check to make sure you have enough fuel and the filter is not clogged. Other issues could be the fuel pressure regulator and fuel pump.
• Check the Ignition Coil - There are a number of tests you can perform on the ignition coil. The first is visual to look for any cracks or deterioration. You can also check the voltage at the coil primary and make sure there is a spark from the coil.

These issues are not the only reasons a car will not start, although they do cover the majority of cases and are a good place to start with troubleshooting, especially if you are newer to refurbishing and owning vintage cars.

Finding Replacement Starter Parts

While all of the parts involved in getting your antique car started are relatively durable, they will go bad eventually. A vintage car with original wiring, parts, and fuses are more likely to experience issues, as is a daily driver classic car that already has newer parts.

The parts that will often go bad include the:

• Solenoid Relay
• Starter
• Ignition Coil

Replacing these generally requires sourcing parts that are specific to your car and engine type. Car makers altered measurements and capabilities every few model years, and the parts also varied by make. Performance is also an important consideration when replacing parts in your vehicle’s ignition system as higher powered engines will require starters and ignition coils designed for those types of systems.

Our inventory at Vintage Auto Garage includes starters, relays, ignition coils, and all the other parts you need to restore and repair antique cars. We carry individual parts and starter kits for almost every model and year. You can find the parts to repair a car that won’t start here on our website or call our team who can advise you on the right parts for your specific model.