What to do when your old car won't start

What should you do if your car won’t start?

If your car won’t start, listen before you do anything else. Silence, rapid clicking, one heavy click, or normal cranking that never catches each point somewhere different: the battery, the starter, the fuel supply or the engine itself. Check the cheap causes first (terminals, a jump, the fuel gauge), then price the repair against what the car is worth.

What to check first, in order

Work down this list. Each step either finds the problem or rules out something cheaper than the next.

1. Turn the key to “on” without cranking and look at the dash. Bright warning lights mean the battery has some charge left. Dim lights, or none, point at the battery or its cables. A key or security symbol that flashes or stays lit can mean the car isn’t recognizing the key, so try the spare if you have one.
2. Turn it over and listen. Rapid clicking usually traces back to the battery. A single click while the lights and radio work points to the starter motor or its solenoid, according to Cars.com’s breakdown of the two. Slow, labored cranking on a cold morning is the battery again.
3. Check the battery terminals. Look for crusty buildup and wiggle each clamp by hand. Vibration loosens them over the years, and cleaning corrosion off the terminals can be enough to restore the connection.
4. Try a jump start. If it fires on a jump, the starter and fuel side are probably fine. If it starts on a jump and is dead again a day or two later, the battery isn’t holding a charge or the alternator isn’t recharging it.
5. If it cranks at normal speed but won’t catch, think fuel. Check the gauge. Then turn the key to “on” and listen for a short hum from the back of the car as the fuel pump primes. No hum can mean a blown fuse, a bad relay or a dead pump.
6. Stop before you flatten the battery. Long bursts of cranking drain whatever charge is left. If the car has a timing belt that’s past its replacement interval, quit and have it checked.
7. Get a diagnosis in writing. A mechanic’s written diagnosis and quote is what you’ll need for the fix-or-sell decision below.

A car that won’t start isn’t automatically junk. What makes a car junk explains where that line sits, and it usually comes down to what the fix costs next to what the car is worth.

Battery, starter, fuel or engine: what each one means

The four usual suspects aren’t equal. Two are routine repairs on almost any car. The other two can end an old car’s life.

Is it the battery or the starter?

Rapid clicking, dim dash lights and slow cranking say battery. One solid click with bright lights says starter. That’s the short version, and it holds most of the time.

Batteries fail for dull reasons: a dome light left on overnight, a cable clamp that worked loose, or plain age. Cold makes all of it worse, because a cold battery delivers less current at the moment the engine needs more. If your no-start happened on a January morning, the winter checklist for older cars has AAA’s figures on how much strength a battery loses in the cold, and the other checks worth doing before the next freeze.

A failing starter often drops hints first: a single click now and then before the car catches on a later try.

Why won’t my car start when it has power?

If the lights, radio and wipers all work and the engine cranks normally but never fires, the battery is doing its job. The engine is missing fuel, spark or compression. Samarins.com, a long-running car repair reference, lists a bad fuse or relay, a failed fuel pump, a faulty crank or cam sensor and an ignition coil pack among the usual causes, along with an engine that’s simply flooded with fuel from repeated tries.

An empty tank belongs on that list too, especially in a car whose gauge you stopped trusting years ago.

So does wiring that rodents have chewed through, which can stop a car from starting or switch on the check engine light. Droppings under the hood are the giveaway, and the guide to rat-chewed wiring covers whether insurance will pay. A hybrid that won’t go is a different case again: the dead hybrid battery guide starts with the battery warranty.

When the engine itself is the problem

This is the expensive branch. The ones that end cars:

• A timing belt that skipped or snapped. On an interference engine, Samarins explains, a skipped belt can let the valves get bent, and a belt that breaks while driving can also damage pistons and the cylinder head. If it lets go on the road, the engine stalls and leaves you stranded.
• Low compression from worn rings, a blown head gasket or burned valves. The engine cranks but can’t build the pressure it needs to run.
• Water in the engine after the car sat in a flooded street. Water pulled in through the air intake can fill the cylinders, and the advice Consumer Reports passes on is not to try starting a car that’s been in flood water. The water damage guide covers what that does and what to do first.

Is it worth fixing a car that won’t start?

It depends on which of those four you’re facing. A battery or a corroded cable is cheap enough that fixing it is almost always right. A starter on a car that’s otherwise solid is usually worth it too.

Engine trouble on an old car is where the answer flips. Put three numbers side by side: the repair quote, what the car would be worth running once it’s fixed, and what it’s worth today as it sits. Add anything else the mechanic flagged while the car was on the lift (tires, brakes, a rusty exhaust), because those bills are coming either way. If the repair eats most of the running value, you’re paying to own the same tired car again.

Our guide to whether a car is worth scrapping walks through that comparison with the cost of keeping a car, not just fixing it. For a sense of what the big repairs cost, the most expensive car repairs are laid out with dated, sourced price ranges.

Selling a car that won’t start

You don’t have to get it running to sell it. We buy cars that don’t start, along with trucks, vans and SUVs in the same state. Lost keys don’t stop the sale either. Tell us about them when you call, so the truck shows up ready to load a car that can’t be started or steered.

A few things that matter when the car can’t move under its own power:

• The tow is free. Nothing comes off the offer to cover it.
• It can be collected where it died. A driveway, the street, a repair shop or an apartment or HOA lot all work, as long as you’ve cleared it with whoever controls the space.
• You’re paid before it leaves. Cash, Zelle, Cash App or another digital payment, at pickup.
• The number holds. Our offers don’t expire, so you can get one now and still wait for the mechanic’s quote before deciding.

If the car is wrecked, burned or stripped as well as dead, the scrap car removal page explains what each condition changes at pickup. And if you’ve already decided, send the car’s details through the two-step form or call (708) 663-1010 between 6 a.m. and 9 p.m. any day. Same-day pickup is often possible across Chicago, the Cook, DuPage and Will County suburbs and Northwest Indiana as far as Gary. More on how we buy cars that don’t run is on the home page.

Sources for this guide

• Cars.com, “Car Clicks But Won’t Start? 5 Common Causes”: rapid clicking vs a single click, loose and corroded battery clamps, battery, alternator and starter causes.
• Samarins.com, “Engine cranks but won’t start: 10 reasons”: fuse, relay, fuel pump, sensor, coil pack and flooded-engine causes; listening for the fuel pump; timing belt skip and bent valves.
• Samarins.com, timing belt glossary: what a broken timing belt does to an interference engine.
• Consumer Reports, “Your Insurance Company Totaled Your Flooded Car”: water entering the air intake and cylinders; don’t start a flooded car.