How to Spot Symptoms of a Bad Starterby Richard RoweUpdated July 05, 2023
A modern starter is composed of two primary parts: the primary motor that turns your crankshaft and starts your engine, and the solenoid that simultaneously engages the starter's drive gear and closes the main motor's hefty electrical contacts. Built for ruggedness and durability, starter motors and solenoids don't typically fail outright. Instead, most modes of starter failure will trigger a number of symptoms that range from somewhat-indicative to almost-definitive signs of a bad starter.
1. Watch Dashboard Lights
Attempt to start the car with the ignition switch, and pay attention to the dashboard lights in your instrument panel and interior. Electric motors, supplied with a certain voltage, will always try to spin at a given speed. If the motor's internal wiring develops an internal short -- one wire connects to another inside -- the wiring will draw more amperage from the electrical system than it otherwise would. This will draw energy from the rest of the system, most noticeably, the lights. If not, there might be a starter relay.
2. Listen for Chugging Sound
Listen for a chugging sound while cranking the car starter. While a certain amount of chug is normal, particularly at low cranking speed, a chug accompanied by dimming and brightening lights may indicate a mechanical failure in the motor's bearings rather than an issue with a electrical component. If this is the case, you may be able to get by for a while by hitting your starter with a hammer from underneath in order to break the starter shaft loose. But, probably not. This could be a failing starter.
3. Listen for the Solenoid Click
Listen for the solenoid click. Starter solenoids typically let off a very noticeable click when they engage; this is the sound of the gear drive engaging and the electrical contact closing. If you hear a click, you can all but rule out the solenoid as a mode of failure. A series of rapid clicks indicates a solenoid rapidly engaging and disengaging. Most of the time, this indicates a lack of power from the battery, but it can indicate a problem with the solenoid.
4. Listen for Grinding
Listen for grinding and freewheeling. A grinding noise indicates that the starter's drive gear isn't disengaging from the flywheel's gear teeth, or isn't engaging the flywheel completely. This is a symptom of a bad starter. Along with or separate from grinding, you may hear a whirring after starting that sounds something like an electric motor or jet engine. The starter's drive gear has a freewheeler in it that keeps your engine from over-running the starter motor and driving it like a generator. The whirring or clicking sound you hear is the sound of the gear failing to disengage, which may indicate a bad return spring or solenoid.
5. Test Battery and Alternator
Have your car battery and alternator tested. There's no sense checking the voltage yourself; even a completely fried battery can exhibit near-normal voltage while not cranking, and you have no way of knowing exactly what the voltage drop should be while cranking. The simple route here is to remove the battery (if necessary) and have it tested at your local auto parts retailer. Or you could try to jumpstart the starter system with jumper cables in the case of a dead battery. But, even if you have a bad battery, don't assume that's the sole cause. A starter with chronic high-amperage draw can drive the last nail into an old battery's coffin, and kill a new one. Simply replacing the battery may solve the problem for a while, but a bad starter will eventually kill the new one, too.
If all else fails, take it to an auto repair shop. It could be anything from an oil leak to a short circuit, and troubleshooting the starting system and ignition system on your own can be difficult.
Video: How to Spot Symptoms of a Bad Starter
Helpful comments from the video:
- Finally a clear concise car repair video that is actually informative
- When you're checking the headlights and they dim when you attempt to crank over the engine, this is perfectly normal. The lights dim momentarily because the amount of amperage required to start the engine is excessive and will also cut radio power as well. This is perfectly normal as starting your engine is the heaviest demand on your battery and therefore the headlights and radio power will be sacrificed in order to allow the amperage of the battery to send the required power (amperage) to your starter in order to turn over (start) the engine.
- This is such a helpful video! My engine didn't turn over, but everything from the lights and all the electrical seemed to be working. When you know it's not your battery and you know it's not your alternator, it's very likely your starter. In my case, I assumed that the starter was supposed to make grinding sounds when it's about to go. Not always! Sometimes it's just very quiet and doesn't turn over at all, which probably means the issue is more related to the solenoid than the inner workings of the starter. In either case, you need to replace it, because the solenoid is often combined as one part with the starter. WOW!!! The tapping or pounding totally works!! Your car will start right up even if the starter is about to go bad. Pounding the starter is much easier and cheaper than calling a tow truck. But for peace of mind, replace your starter ASAP. If you're not sure how to find the starter on your specific make and model, just do another search. There are lot's of helpful videos like this one.
Richard Rowe has been writing professionally since 2007, specializing in automotive topics. He has worked as a tractor-trailer driver and mechanic, a rigger at a fire engine factory and as a race-car driver and builder. Rowe studied engineering, philosophy and American literature at Central Florida Community College.