Why is my check engine light flashing?
It’s every car owner’s worst nightmare. You’re driving down the road-- everything seems to be fine-- when, out of nowhere, your check engine light comes on.
Your check engine light can be triggered by a number of things. Even if your car seems like its driving just fine, you should still make time to see a mechanic as soon as possible. Neglecting a minor issue could lead to bigger, and more expensive, problems down the road; you may be wasting fuel, putting out lots of pollution, or damaging the engine without even realizing it.
A blinking light or, on some cars, a red light (instead of a yellow light) indicates a problem that needs immediate attention. Here are some potential causes, and what you should do about them:
Your gas cap is loose.
If you’re just pulling away from the gas station and suddenly notice the check engine light, it is probably just an alert from your car that you forgot to close the cap. Find a safe spot to park your car, and check to make sure that both the gas cap and door are tightly closed. If that doesn't do the trick, you should call your mechanic right away.You have a faulty sensor.
Over time, dirt and debris will build up on different parts of your car, including sensors. This residue can trip up a sensor and create an alert. Some sensors are especially vulnerable, like your oxygen sensor which monitors your gas mileage and emissions, or your airflow sensor which tracks how much air is passing through the engine. Luckily, certified technicians can use the code from the check engine light to quickly identify and replace the sensors.You blew a head gasket.
The head gasket forms a seal between the engine block and the cylinder head. Most of the gasket can’t be seen without disassembling the engine so a blown head gasket can be very difficult to diagnose-- and expensive to replace. Here are a few visual cues to look for:- Coolant leaking from below the exhaust manifold
- White smoke coming from the exhaust pipe
- Bubbles in the radiator or coolant overflow tank
- Overheating engine
- White milky oil
- Fouled spark plugs
Your spark plugs or spark plug wires are worn out.
Spark plugs trigger combustion in the engine. An engine with properly performing spark plugs should make a continuous and smooth sound. Deteriorated spark plugs can cause misfiring during acceleration that makes rough, jittery sounds when your engine is running and decreases your vehicle’s fuel economy due to incomplete combustion. Spark plug longevity depends on the condition and type of spark plug you currently have so it's important to make sure they're checked frequently and replaced if needed. Some other symptoms include:- Engine Misfires
- High Fuel Consumption
- Lack of Acceleration
- Rough Idle
- Problem Starting Your Car
You have lose or cracked hoses and manifolds.
Your car has two manifolds – an intake manifold and an exhaust manifold. Both are essential parts of your vehicle, but the exhaust manifold is far more likely to experience problems. Exhaust manifolds are subject to intense heat, which means they’re also subject to expansion and contraction which, in turn, leads to metal fatigue. If your exhaust manifold is leaking or cracked,- Incorrect back pressure in the exhaust system
- Reduced engine power
- Engine “sputtering”
- Failed emissions testing