It’s annoying when your car refuses to switch off after the key is removed from the ignition. But you have no choice, you need to fix it as soon as possible. Don’t worry! We extensively researched all the ways to help you fix the issue.
When you experience difficulty in turning off the car engine even after the key is out, you might have electrical or dieseling problems. Following are the things you need to examine to solve the issue:
- Electrical Problems
- Ignition Switch
- Power Relay
- Dieseling Problems
- Carburetor/Fuel Injector
- Idle Speed
- Anti-Dieseling Solenoid
- Ignition Timing
- Spark Plug
- Built-up Carbon
In this article, we look at why your engine won't turn off when removing the key and what you can do to resolve the issue. Continue reading for more details.
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Common Reasons Why Car Won’t Turn Off Even With Key Out
You expect the automobile to stop when you turn off the key! When it doesn't, it can be confusing and aggravating. If the engine continues to operate as if you had never shut it off, the following might be the reason:
Defective Ignition Switch
One of the most important parts of your vehicle is the ignition switch. The ignition switch is usually located next to the ignition lock cylinder on the steering column.
The ignition lock cylinder is the keyhole into which you insert your keys to turn on and off the ignition switch. Both the switch and the cylinder will not work properly if the ignition switch is defective.
However, because the ignition switch is used frequently in your vehicle – sometimes multiple times per day – it will ultimately wear out and break down.
Broken springs, worn ignition switch contacts, and temperature issues are just a few of the factors of the defective ignition switch.
Faulty Fuel Pump Relay
You can think of a fuel pump relay as a large fuse. They all work on the same concept, and you probably have a couple on your automobile.
The primary relay controls the car's computer and the gasoline pump. None of your devices will work if the main relay fails.
While a fuel pump relay might fail due to a short or other electrical failures, the most common reason for a broken or damaged fuel pump relay is age.
Every time the relay clicks over, it wears a little bit more, and after more than 100,000 miles, that's a lot of clicks.
It will eventually become too much for it to handle, and it will either not click over again or will not return to its initial place. It's perfectly normal, and as long as it doesn't happen frequently.
Dieseling gets its name from the way diesel engines work: they fire without a spark. Instead of a spark, a diesel engine's ignition source is the heat produced by the cylinder's air compression.
The dieseling occurs not only because the compression ratio is high enough for the fuel to self-ignite, but also because a location inside the cylinder (combustion chamber/valve edge, spark plug electrode, or even extra carbon) ignites the gasoline.
After being shut down, a vehicle engine will run for a few seconds or minutes, sputter, and then gradually cease, depending on how much gasoline is left in the combustion chamber and how long it takes for the ignition source to cool down.
This is most common in carbureted engines with a lot of miles on them. If a petrol-powered engine starts to die, something is amiss.
The possible reasons for dieseling are faulty carburetor, the idle speed that is too fast, broken solenoid, incorrect timing, improperly rated spark plug, and built-up carbon.
Fixing a Car That Isn't Turning Off Even With the Key Out
There are a couple of measures you can take to figure out what's going on. With a few modest changes, you might be able to solve the problem.
1. Examine For Any Electrical Problems.
The turn signals and accessories continue to work after the car key is turned off or out. Also, when you put your car in gear and drive away, the engine works smoothly.
If this is the case, your vehicle may have electrical problems. Proceed to the next step if this is the case. If not, proceed to number 4.
2. Examine The Ignition Switch For Any Defects.
Remove part of the plastic shroud that surrounds the steering column. Locate the ignition switch's electrical connector. It could be on the rear of the ignition switch, or it could be lower down the steering column at the end of an electrical pigtail from the switch.
If you unplug the switch at the connector, everything should turn off right away. But If it does not turn off after what you did, this means your ignition switch has a defect and needs to be replaced. If this is not the case proceed to the next step.
An actual demonstration of replacing the ignition switch is shown on YouTube below.
3. Examine The Power Relay.
It's possible that your car's engine will function correctly after the ignition switch is disconnected. If that's the case, you'll need to find the ignition and fuel system's power relay.
Remove the primary relay and see if your automobile shuts down completely. If it stops working, you'll need to replace the primary relay. If not, proceed to the next step in the troubleshooting process.
A video from YouTube is shown below to show you how to pull out the relay from the fuse box.
4. Check If It Is A Dieseling Problem.
If the engine does not stop and instead appears to go into leaping spasms with knocking and pinging sounds, this is referred to as "dieseling". Following are the troubleshooting ideas.
4.1. Examine If It Is Carburetor Or Fuel Injected.
Is your vehicle equipped with a fuel injection system or a carburetor? Check your workshop manual if you don't know. Fuel injection is likely in your car if it was manufactured after 1985.
Fuel injection rarely causes dieseling since the fuel delivery is stopped as soon as the switch is turned off. A carburetor will deliver fuel as long as there is air moving through it unless it is specially designed. If your fuel-injected vehicle is dieseling, the system has a leaking fuel injector that needs to be replaced.
4.2. Examine The Idle Speed
If the engine idle speed is too high, the automobile may diesel after it has been turned off. Check your idle speed by connecting your tachometer according to the instructions.
Idle speed for most four and six-cylinder engines should be between 850 and 900 RPM. Engines with eight cylinders may idle at 600 RPM. Check your workshop manual for specifics on how to set the idling speed.
4.3. Examine The Solenoid For Anti-Dieseling.
Dieseling became a problem on even new cars in the late 1970s, with the adoption of emission controls. As a result, manufacturers incorporated an anti-dieseling solenoid into their carburetors.
It's normally cylindrical, around 1-2 inches long, and connected by a single wire. When the key is turned on, that wire becomes hot, opening the valve and allowing it to close when the key is turned off.
Turn on the key and disconnect the wire. Release the connectors by touching them together. As the solenoid opens and closes, you should hear a click. If no sound is heard, the solenoid is broken and has to be replaced.
4.4. Examine The Ignition Timing.
Modern cars do not have adjustable ignition timing, but if your vehicle is old enough to have a dieseling problem, it most likely does.
If the ignition timing is off by a few degrees, the temperature within the engine might rise to the point where it causes dieseling.
The timing process can be found in the manual. It varies greatly from vehicle to vehicle. Some cars have the timing set to idle, while others have it set to a high engine speed.
Before you adjust the timing, some manufacturers require you to disconnect specific controls. There is no universal approach for all engines.
4.5. Examine the Spark Plug.
Dieseling can also be caused by using the wrong spark plug.
Spark plugs are designed to maintain a set operating temperature, and if your engine's plugs are in the improper heat range, they could generate a hotspot, which could lead to dieseling.
Take a spark plug out of the box and check the part number against the manufacturer's specs. If you notice anything wrong with them, replace them.
4.6. Examine The Carbon.
If you've gone through all of these measures and still can't cure your problem, your engine is most likely clogged with carbon.
- Consider adding a fuel additive. There are many fuel additives available on the market that are designed to help remove carbon from an engine while it is operating.
Fill the tank with a fuel additive according to the manufacturer's recommendations. Then drive the automobile on the highway for a while, doing some harsh accelerations.
Carbon deposits will be broken up and sent down the tailpipe with the cleaning mixture.
- Consider replacing your fuel. Using higher octane fuel may assist you to solve a dieseling problem you haven't been able to solve with previous methods.This is a treatment rather than a cure. Higher octane fuels are more stable and less prone to engine pre-ignition caused by carbon buildup.
So if you're stuck with the dilemma of how to turn off a car engine, the above troubleshooting techniques can help. Don't forget to use these useful tips in the future if you run into this difficulty. If you are not comfortable doing it by yourself, hire a certified mechanic from your area to do it for you.
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If your vehicle engine continues to run after the ignition switch is turned off that means the ignition switch is defective and/or the ignition is still being powered from "elsewhere" in the circuit even though the switch is "off".What would cause my car to not turn off? ›
If the engine continues to run just as before you turned it off - as if you hadn't turned it off at all - your ignition and fuel system are not shutting down. In that case, your car has an electrical problem that needs to be addressed. Either your ignition switch element or a power relay needs to be replaced.What causes a car to keep running after turned off? ›
Running-on is when the engine continues to turn after you've switched off the ignition because the fuel /air mixture is being ignited by a hot-spot in the combustion chamber .How do you fully turn off a car? ›
The step-by-step procedure of switching off a car is as follows: Park the car at the place where you want to stop and put the gearbox in the neutral mode. Take your foot off the clutch but don't take the pressure off the service brake. Then, apply the parking brake, release the brake pedal, and switch off the engine.How do you turn off an engine? ›
In a car with a key ignition, turn the key to the off position and remove it from the ignition. In a car with push button ignition, press the start/stop button to stop the engine.How do you force a car to turn over? ›
- If the Car Clicks When Trying to Start. Try Cycling the Key. Try Tapping on the Battery Terminals. Try Tapping the Starter.
- If There's No Click When You Turn the Key. Try Shifting the Shifter.
- If the Engine Cranks But Won't Fire Up. Try Swapping Relays. Try Smacking the Fuel Tank. Try Un-flooding a flooded engine.
Your engine may also overheat if you leave your car idling for too long. However, this particular error often occurs because of mechanical malfunctions. If your engine overheats, get your cooling system or fan belt checked by a certified mechanic. Your car may run out of gas.How much does it cost to fix ignition switch? ›
The Average Cost for Replacing an Ignition Switch Is $98-$215 Depending on If You Go to the Mechanic or DIY. This price range is based on national averages for all vehicles and does not factor in taxes, fees, or your particular make and model.How do I know if my ignition switch is faulty? ›
- Car Won't Start. If you turn your key and the car attempts to start, but fails, then you might have a broken ignition switch. ...
- Key Won't Turn. ...
- Car Stalls. ...
- No Noise From The Starter. ...
- Dashboard Lights Flicker.
Engines operate at their most efficient when they're hot but not too hot. The fan turns on when you've stopped driving because no more cooling air is flowing into the engine bay. This causes the temperature to rise, automatically triggering the fan.
The average car can usually run for around 7-8 hours before you need to stop in order to add more fuel to your car.Will my car turn off without the key? ›
Every push button car I've seen will continue to run once started, regardless of where the keyfob is. However, as others have stated, if you turn the car off and they key is no longer in the car, you will not be able to restart it. The only way the car will “turn itself off” is if it runs out of fuel.How does an engine stay running? ›
The throttle stop allows the butterfly valve to sit ever-so-slightly open, thus allowing for a minimum amount of airflow to reach the combustion chamber. This opening is just enough to allow a specific amount of airflow through to keep the engine running when there is no physical throttle input from the gas pedal.Can you take a turn off your car? ›
However, newer cars have safety features that won't allow you to do so. Regardless, never attempt to turn off a car while driving. When your car turns off, all of the systems shut down. That means that you'll lose power steering, engine power, and antilock brake functionality.How do you manually turn over an engine? ›
The best way to turn your engine over is to place the socket on the front of your engine's crankshaft bolt, which is typically mounted to your crankshaft; then take your wrench and use it to manually roate the crankshaft (turning the wrench in a clockwise motion).How do you turn off a car fast? ›
Pull the starter relay in the fuse box. The engine won't crank and no damage will be done to the car.How long can a car sit before it dies? ›
Typically, your car can sit about four weeks to two months without driving before the battery dies. The reason your car can sit only for so long before it dies is the fact that your car battery is in use even when you're not behind the wheel.How long can a car run just sitting? ›
How Long Can You Let Your Car Idle? Idling your car for 30 seconds to a minute is acceptable, and it will not cause any harm to your vehicle. With advanced technology, even if you let your car idle for a slight longer duration, it will not damage it.What to do with a vehicle that has been sitting? ›
- Making sure that the engine is free to rotate.
- Clean oil.
- Lubricating the cylinder walls.
- Clean air.
- Clean fuel.
- Clean coolant.
- Intact fan belt.
There are several reasons why your vehicle's ignition switch may fail. Some of these include broken springs, worn ignition switch contacts, and temperature problems, which may prevent you from even getting your vehicle out of the garage.
You can replace the ignition switch yourself, but it's not an easy task: you will have to remove the steering wheel and work close to the airbag - which can be dangerous. Don't hesitate to call a professional mechanic if you're not feeling confident.How long do ignition switches last? ›
For decades, all the car part information a person could find would recommend the replacement intervals for ignition system components, usually at the 30-, 60-, or 90,000-mile (48,280-, 96,561-, or 144,841-kilometer) tune-ups.How do you bypass an ignition switch without the key? ›
Use a portable jump starter or use another car to jumpstart your vehicle. Either with a portable jump starter or with a jumper cable connected to another car. It's pretty easy to jumpstart your vehicle. All you have to do is connect to identify the ignition coil and the battery.Can a faulty ignition switch drain your battery? ›
This causes the fuel to work and gives the power your car needs to run. A typical problem with the ignition switch is when your car fails to start. This sign forces you to keep making attempts to turn the engine, draining and, therefore, killing your battery. At same time, idling your car can also cause a stalling.What to do if fan keeps running? ›
If your fan limit switch is set to AUTO but the fan continues to run without ever stopping, you'll need to call a professional. Two problems that could cause your fan to run without stopping include: A bad fan limit switch that needs to be replaced. Bad thermostat wiring.Can low coolant cause fan to stay on? ›
If your engine coolant's too low, it means that the cooling fan will have to work harder to keep the engine at a normal temperature. To check the level, look for the coolant expansion tank in the engine bay. There are usually two marks on it – a minimum and maximum level mark.How do you know if your engine fan is bad? ›
- Engine Overheating. When the radiator fan isn't functioning properly, it is not able to adequately cool down the car's engine. ...
- Air Conditioner Function Diminished. ...
- Loud Noise Coming From Radiator Fan.
When should I let the engine cool down? While turning off the engine immediately for naturally aspirated vehicles doesn't cause problems, you will need to give a forced induction motor (turbocharged) a few minutes to cool down. This cool-down period won't take too long as a couple of minutes is all that is needed.What happens if you leave your car running for 8 hours? ›
J.R. Ray: Well, to answer your first question, leaving the car running all day won't do any damage. As long as the engine's cooling system is working normally, a modern car can run for days and days -- until it runs out of gas -- without causing itself any harm.How long can a car battery last? ›
Some cars will get up to five or six years out of their battery, while others will need a new one after only two years. In general, your car will usually need a new battery after three to four years. Replacing your car battery is another part of routine maintenance.
In modern vehicles, you cannot remove the key with the engine on. Even if you can do it due to some defects, you will lock the steering wheel. As it will happen while the car is still running, an accident seems almost inevitable.How long will a car stay running without the key fob? ›
If a vehicle equipped with Extended Parking is left running with the transmission in Park and the keyfob is not present, the whole thing shuts down after just 30 minutes of idling. Even if the car's key fob is present – in the cupholder, on the seat, in your pocket – the car still shuts down after 60 minutes.How long will a car run without the key? ›
Generally you can keep driving until you turn off the ignition. Then you need the fob again to restart the car. Some of the keyless ignition cars will start with the key more than 50 ft from the car…Will disconnecting battery clear my key? ›
However, disconnecting your car's battery for a few minutes and reconnecting it may help to reset the key fob.