The check engine light is flashing when the key is in the on position. These are the causes

Flashing lights on your dashboard as soon as you put the ignition in ON position can be disheartening; the engine is not even on yet. Sometimes the check engine light illuminates when the key is in ON position to reveal some underlying conditions.

These conditions vary from mild battery power transmission issues to important engine and car computer components damage.

Some of the conditions that cause this kind of behavior include loose fuel caps, faulty catalytic convertors, and powerless batteries.

We will delve deeper to expound further on the reasons why the check engine light is flashing when the key is in the ON position.

Loose Fuel Cap

It is quite rare for there to be any serious issues with the engine when this light comes on especially if the engine is not even on yet.

Most of the time, the problem can be traced to the fuel cap. If you ever experience this issue please check the gas cap before calling the mechanic.

When this rather minor car part is loose or broken, other more delicate components will face the blunt. This will trigger car sensors that reflect on the dashboard.

Some of these delicate car parts include the emission control sensor which will be duped into detecting a fuel leak-this is due to the extra air present in the gas tank which is caused by the loose gas cap.

Immediately tighten the fuel cap and check for improvement after a few minutes.

Faulty Catalytic Converter

A bad catalytic converter can cause the engine light to flash. This is pretty obvious maybe due to the severe engine damage that can result from using a bad catalytic converter.

You will notice the flashing light and if you choose to go ahead and drive the car other symptoms will show. The car will become sluggish, the exhaust smoke will be darker, and any attempt to make swift acceleration will be thwarted.

The only solution for a bad catalytic converter is a replacement which we must say is anything but cheap. The cost varies though depending on the car model and the rapier shop’s rate.

Bad Air Flow Sensor

The car runs on two things, fuel, and air. If the delivery of either is interrupted, you can expect lights to flash around.

The most affected part is the airflow sensor which when not regularly checked could easily break. It will cause the engine light to come on but this should not be a reason to worry.

You can still start the car and drive away but other aspects of the car like fuel economy will be affected. You can however save yourself the trouble by having the airflow sensor replaced at any accredited repair station. The procedure is quick and not so expensive.

The next time you visit the mechanic, ensure to have the airflow sensor checked.

Bad Spark Plugs

This is not common in modern cars-their spark plugs are built to last almost as long as the car. High mileage models are however not so lucky. Their spark plugs are susceptible to failure at any stage in the car’s existence.

The signs that come with bad spark plugs are sometimes similar to those of other car problems so you are advised to check for other conditions before you convict the spark plugs.

The good thing however is that you can easily swap spark plugs in different cars but this is only for experienced drivers. Newbie car owners are advised to have a mechanic do it for them.

The Oxygen Sensor Could Be Damaged

The O2 sensor works more like the airflow sensor only that it monitors the amount of oxygen that leaves through the exhaust.

A damaged O2 sensor will not ground your car but driving with it could easily damage the catalytic convertor which as we stated above is pretty expensive to repair.

Another immediate and direct result of driving with a bad O2 sensor is poor fuel economy. You can have the sensor replaced anytime and at very low costs.

The Engine Might Not Be Warmed Up Yet

If you are starting the car after a long stay in the yard, the engine might take some time to warm up. This will trigger the check engine light to flash.

You can start the car and drive slowly for some time as the warm air runs through the engine. After some minutes the light should go away, if not call your mechanic.

Should I Worry If The Check Engine Light Flashes Before The Car Starts?

The answer to this question is more subtle than concrete. The underlying condition causing the light to flash will determine whether the driver will worry or simply start the car and drive off.

Wrap Up

The check engine light is the first sign modern cars give when something is wrong. If the light flashes with the engine still off, you might get confused.

The good news is that the light rarely signals any serious issues although a quick check is always in order.

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