It can understandably be disconcerting anytime that your check engine light appears. However, it can seem much more sinister if the light is flashing. So, what does it mean if your check engine light is flashing and your car won’t accelerate?
If your check light is flashing and the car won’t accelerate, it is a sign that your spark plugs or engine sensor are bad. This can also indicate that your fuel injector or ignition coil stopped working. You also won’t be able to accelerate if there is a vacuum leak in your engine or if your head gasket is blown.
Your check engine light can also flash if there is a fuel, coolant, or oil leak. Turn your car off if the check engine light is flashing to avoid further damage. Follow along as we explore what it means when your check engine light is flashing and the car won’t accelerate.
What Does The Check Engine Light Status Mean?
Flashing Check Engine Light
A flashing check engine light is generally more serious than one that stays on. This typically indicates that your car’s engine is misfiring. You should stop trying to start your car if you see a flashing check engine light.
This indicates that there is something wrong with the air-to-fuel ratio in your engine as well. It can also point to problems with your spark plugs, fuel injector, ignition coil, and head gasket. Turn your car off if you see a flashing check engine light and contact an auto shop.
The Check Engine Light Stays On
If your check engine light stays on, it’s typically a sign that there is a problem with your ignition system. However, the most common reason why a check engine light stays on is that you need an oil change. Otherwise, it could be a sign that it wasn’t reset after you recently maintained your car.
You can check for trouble codes if you use a code scanner. This can save you time and money so that you don’t have to go to an auto shop. A trouble code scanner can also help you communicate with professionals and get quick service so that they don’t have to diagnose the problem.
Can I Ignore The Flashing Check Engine Light?
You should never ignore a flashing check engine light. This can pose a serious risk to your car’s condition and even your safety. The light only flashes if there is a serious problem, so it’s not worth risking causing worse damage.
You can wait to bring your car to a shop if the check engine light is static. However, a flashing light is a sign that your engine is in trouble and it is dangerous to ignore. You shouldn’t even drive your car to a shop if the check engine light is flashing. Instead, you should use a roadside assistance service or tow your car to the shop.
What To Look For When Your Check Engine Light Is Flashing
Check for oil and coolant on the ground underneath your car when your check engine light is flashing. There is a strong chance that there is a leak somewhere within your engine or coolant system. You should also pop your hood and check for steam, smoke, and excessive heat.
Fuel can even leak from your exhaust system and trigger your check engine light to flash. This is a dangerous situation and you should turn your car off right away. Let your car cool down and check your spark plugs for damage.
The least dangerous situation is that you simply lost your gas cap. However, the check engine light is static in that case more often than not. Contact a professional if you cannot identify any obvious problems right away.
Common Causes Of Check Engine Light Flashing and Car Won’t Accelerate
Everything from a leaking head gasket to a bad fuel injector can explain why your engine light is flashing and the car won’t accelerate. Sometimes, the cause is as simple as a lack of fuel in your engine. Let’s take a look at the most common reasons why your check engine light is flashing and your car won’t accelerate.
Bad Ignition Coil
The ignition coil, or spark coil, helps transform your battery’s voltage to help start your car. Ignition coils are necessary for the spark plugs to work. When an ignition coil goes bad, your spark plug won’t be able to ignite the fuel in your engine.
You should see your check engine light flashing on when this happens, and your car won’t accelerate. Over time, an ignition coil can go bad due to prolonged physical trauma. This is common if you frequently have to drive over rough roads.
Heavy vibrations can rattle your ignition coil and eventually hinder its performance. Otherwise, an ignition coil can wear out after 100,000 miles.
Bad Fuel Injector
Your car won’t accelerate if you have a bad fuel injector. As the name suggests, the fuel injector injects the fuel into your engine’s intake manifold. The check engine light will come on if this component goes bad because your engine won’t get the necessary fuel.
Without fuel in the engine, you cannot accelerate, and you will be stuck until you replace the part. Clogged and damaged fuel lines can eventually affect the fuel injectors. This can cause them to become dirty and worn or stop working altogether.
You will likely smell a strong fuel odor as well which can help confirm that the injector is the problem. Even just a single bad fuel injector will result in a flashing check engine light or even white smoke on startup.
Lack Of Fuel In The Engine
A lack of fuel in the engine can throw off your car’s entire system. Your check engine light will flash, and you won’t be able to accelerate because there is nothing to ignite. This can happen due to mistakes such as forgetting to refuel.
However, it can also point to serious problems such as a leak in your gas tank. You can tell that the latter is the problem if you find gasoline in and around other key parts of your car. Generally, you will smell gasoline as it leaks whether you are inside or outside of the car.
Otherwise, your car may simply think that there is no fuel in the system. This can happen if you use the wrong kind of fuel or if your car’s fuel sensor is bad.
Faulty Engine Sensor
Engine sensors keep track of everything from the temperature of the coolant to the composition of your car’s exhaust. More importantly, the engine sensor also regulates how much fuel is necessary for each of your car’s functions. Without a working sensor, your car cannot evenly distribute fuel to run your engine, AC system, and even your radio.
The engine sensor in your car is durable, but it is also exposed to plenty of contaminants. Combustion creates byproducts that can easily clog, coat, and damage your engine sensor. A clogged or damaged engine sensor cannot communicate with your car’s computer.
Luckily, your check engine light will flash so that you know that there is a problem. It’s important to replace it right away so that your engine doesn’t misfire.
A Leaking Head Gasket
Head gaskets are a critical part of any car because they help maintain engine pressure and prevent leaks. That said, head gaskets are prone to leaks, which can explain why your car won’t accelerate. You will also see your check engine light flashing when this happens.
Never drive your car when the head gasket is leaving if you are somehow able to accelerate. This can be quite dangerous. Leaks occur when your engine overheats, and your engine block expands. The expansion will create a gap that lets oil and coolant leak out.
Unfortunately, the only solution is to replace your head gasket because you cannot repair them. Always check for leaks under your car when it’s parked so that you can catch a leaking head gasket early.
A Vacuum Leak
A vacuum leak is a common problem for many car owners, and it can explain why your car won’t accelerate. Your check engine light will also come on when this happens, and it will produce a fault code. Vacuum leaks are a problem because the intake manifold can take on air that it doesn’t need.
Ideally, your engine should create a self-sustainable vacuum because of the piston movements. This isn’t possible when there is a vacuum leak, and your car can get stuck. A check engine light is typically the first sign of a vacuum leak in your car.
Your car may have difficulty running and starting before the check engine light comes on. Vacuum leaks can happen due to a damaged intake manifold, brake booster, or gasket.
Engine Isn’t Warmed Up
It can be harmful to your car to drive when your engine isn’t warmed up. Your engine needs to warm up so that the oil can get everywhere that it needs to go before you drive. Over time, it can be harmful to your car’s overall health and engine if you drive away immediately.
The oil can also get cool and will move too slowly throughout your car if you don’t let your car warm up. In extreme cases, you won’t be able to accelerate, and your check engine light will flash. This most commonly happens when it is extremely cold outside.
How To Fix a Check Engine Light And Car Not Accelerating
It’s important to address the problem right away when your check engine light is flashing and your car won’t accelerate. Solutions such as replacing your engine sensor or key parts of your fuel system can often solve the problem. Let’s explore how to fix a check engine light when your car won’t accelerate.
Bad Engine Sensor
You need to replace your engine sensor if it is worn and bad. It costs an average of $60 to replace an engine sensor, but it can cost up to $100. However, you may spend as little as $20 if you replace the part without professional help.
Oil And Coolant Check
Leaking oil and coolant can trigger your check engine light, and you’ll need to replenish both. It costs an average of $150 to professionally replace the coolant in your car. You may also need to get an oil change which generally costs between $30 and $80.
Check For Vacuum Leaks
Check to see if your engine has a vacuum leak by spraying water on the engine. Water will suck into the engine if there is a vacuum leak. You can expect to spend up to $130 to fix an engine vacuum leak.
Check For Fuel System Problems
Inspect key parts of your fuel system for problems, such as the filter, injector, and pump. Each of these parts will trigger your check engine light and prevent acceleration if they fail. Even the fuel tank itself can be the cause, and you may need to flush it with air or water.
Spark Plugs Need To Be Checked
Spark plugs are essential to your car’s ignition system and can stop your car from accelerating. Turn your car off and carefully inspect your spark plugs for debris. Remove the debris if it isn’t too bad, or replace your spark plugs for $15-$20 each.
Can Bad Spark Plugs Cause Your Car Not To Accelerate?
Bad spark plugs can prevent your car from accelerating. Engines need spark plugs to ignite the fuel so that your car can run. Spark plugs go bad when they overheat or become clogged with debris, and they can’t create a spark to ignite the fuel.
When I Step On The Gas My Car Hesitates
It often indicates that there are contaminants in your fuel if you step on the gas and your car hesitates. This can also happen if your engine has a vacuum leak or if your throttle position sensor is worn. You can expect to spend between $100 and $200 to replace a throttle position sensor.
Can A Bad Fuel Filter Slow Acceleration?
Fuel filters become dirty and clogged which can slow acceleration. This happens naturally over time because of the byproducts of fuel combustion. Ideally, you should replace your fuel filter every 30,000 miles or sooner if you notice a problem.
Ask a Professional
Professionals are best equipped to help when your check engine light is flashing and the car won’t accelerate. Most fixes, such as adding coolant and oil cost $100-$200 or less. You may spend as little as $15 if you simply need to replace a single spark plug.
Unfortunately, you may have to spend between $800 and $1,900 if you need to replace your head gasket. It’s worth the cost if your car will be able to run for at least another 10,000 miles. Call an auto shop if your check engine light is flashing and your car won’t accelerate.