- Reasons
- Fixes
- FAQs
Car revving refers to pressing the accelerator and increasing the engine’s Revolutions Per Minute (RPM) when the vehicle is stationary or neutral. It is generally performed by drivers to warm up the engine, providing it with more fuel and air. However, a car revving on its own when driving or stationary reflects malfunctioning auto parts. That said, these malfunctioning auto parts can cause significant damage to the car and, in extreme cases, might cause accidents. This is why it is necessary to cater to the car revving on its own immediately.
Prior to seeking professional assistance, let’s first understand how a car keeps revving on its own while driving or stationary and how to fix it.
Reasons Why Car Revving on Its Own
Proper car revving aids in avoiding many issues like carbon buildup and engine misfires. However, involuntary car revving shows that one or more engine parts are faulty. It can occur due to defective auto parts, manufacturing problems and a few other reasons listed below.
Faulty Spark Plug
The spark plug plays a vital role in a vehicle’s ignition system, as it provides the spark to ignite the air and fuel mixture inside the combustion chamber. A bad spark plug will cause difficulty in starting a car, uncontrolled acceleration and engine misfiring, leading to the car revving on its own when stationary or driving.
Bad Idle Speed Control Valve
The idle speed control valve or idle speed control system is used to maintain an adequate idle speed of an engine. The idle system ensures smooth and consistent idling when the vehicle is stationary.
If dirt and grime build up on the idle air control valve, it can cause stationary vehicles to accelerate and rev autonomously. It can also happen when the idle control valve is defective and deteriorates with time.
Clogged Air Filter
The engine air filter is responsible for cleaning all the impurities from the air before passing it to the combustion chamber. If the air filter is not changed periodically, impurities clog the filter, disrupting the airflow. To balance the disrupted airflow, the Engine Control Unit (ECU) increases throttle opening, causing cars to rev on their own.
Air filter change is a simple process and can be done at home without any professional assistance. Here is the complete process of changing the car’s air filter.
Malfunctioning MAF Sensor
A Mass Air Flow (MAF) sensor is present between the air filter and intake manifold. The sensor manages the amount and speed of air entering the combustion chamber. Therefore, a malfunctioning MAF sensor can cause airflow disruption, leading to rough idling, excessive acceleration and car revving on its own when stationary or driving.
Obstructed Throttle Body
A faulty throttle body is one of the major reasons that can cause a car to rev on its own when driving or stationary. The throttle body is an air storage chamber that only opens when the accelerator pedal is pressed. Wear and tear can reduce its efficiency, leading to disrupted openings and closing of the valve. That said, it is recommended to clean the throttle body promptly to avoid the hassle.
Defective Fuel Injector
A faulty fuel injector delivers a disproportionate amount of fuel in the chamber, causing autonomous car revving. Simply, a malfunctioning fuel injector causes overabundance or scarcity of fuel inside the chamber, causing car revving, over-acceleration and car stalling.
How to Fix a Car Engine Revving on Its Own
To fix a car engine revving on its own when driving or stationary, it is necessary to identify the malfunctioning part. The first way to identify the culprit is by checking the engine light illuminated on the instrument cluster. Aside from that, drivers can also use an OBD Scanner to identify the faulty part leading to car revving.
It is recommended to seek professional assistance if the malfunctioning part is difficult to replace. Other than that, here are some tips that drivers can follow to avoid car revving.
- Draft a monthly car maintenance checklist and get your vehicle checked regularly. Make sure the list includes oil change, filter change and fuel system inspection.
- Regularly check vacuum leaks, hoses and connections and replace the faulty ones immediately.
- Clean your throttle body at least once every two months to avoid dirt and grime buildup.
- Avoid sudden acceleration and aggressive driving, as it can stress out the engine, causing multiple engine parts to malfunction.
- Use high-quality fuel to prevent carbon build-up inside the engine that can cause a car to rev on its own.
- Do not rest your foot on the accelerator when not actively driving. This can increase the engine’s RPM, resulting in faulty auto parts.
FAQs
Why is my car revving on its own while driving or stationary?
A car revving on its own indicates a faulty auto part like a malfunctioning throttle body, fuel injector spark plug, or clogged air filter.
Is the car engine revving badly?
Yes, it is bad if performed when the engine is cold. Allow the car engine to warm up properly and then rev it. Here is how to rev the car engine properly.
What happens when I rev my car?
When a car engine is revved, it increases the RPM, forcing engine fluids in every corner, warming up the engine and creating a loud sound from the exhaust.
These were all the reasons leading to a car revving on its own when driving or stationary. Car revving indicates a faulty auto part that can be replaced easily. However, if the issue is consistent, it might be due to some major malfunctioning in the vehicle. Rather than fixing the issue and spending a fortune, it’s better to switch to another vehicle. Browse through these used cars for sale in the UAE and choose from an array of options as per your budget.
Stay tuned to dubizzle’s auto blog to learn how to fix an over-revving car.