Vehicle manufacturers have designed a system where if your car emissions go above a certain limit for a period of time, your check engine light can come on. Check Engine light (CEL) can turn out to be one of the most simplest issues or the most complicated issue your car can have. It can be as simple as your gas cap being loose or as serious as a misfire which can be difficult to diagnose.

  • Should I be worried?
  1. Blinking CEL:

If the light is blinking it is advised to stop as soon as you can in a safe manner and have a mechanic diagnose the issue. It is usually because of a severe misfire issue that can cause damage to other components if ignored.

2.  Steady CEL:

A Steady CEL can also be a serious issue but you don’t have to stop the car right away. You should have a mechanic diagnose as soon as possible but you don’t have to stop driving. It is however advised not to drive the car until this is fixed. This can turn out to be a simple or a complicated issue.

What are some of the most common causes?

It can be any of the following:

  • Faulty oxygen sensor:

A faulty oxygen sensor in the exhaust can cause a bad fuel air mixture which can cause an imbalance in the exhaust gases going in the catalytic convertor and potentially damage the catalytic convertor.

  • Faulty spark plugs or wires:

Three things that are needed for the engine are – fuel, air and spark. Faulty plugs can cause faulty sparks or misfire which could also cause the CEL.

  • Faulty mass air flow sensor:

Anything that affects the air, fuel or spark going into the engine can cause a CEL to come on. Faulty mass air flow sensor is one of them.

  • Misfire:

An engine misfire can itself be caused from not appropriate air, fuel or spark when can then become a serious issue and can damage the engine in a big way if not taken care of. For all these issues, it is highly advised to have a mechanic diagnose with special tools to fix these issues as soon as possible to prevent further damage and expensive repair bills.

For all these issues, it is highly advised to have a mechanic diagnose with special tools to fix these issues as soon as possible to prevent further damage and expensive repair bills.

  • How does your mobile mechanic fix this issue? And how can I know it is what the mechanic says it is?

To be able to get see the difference, a test drive before and after with the mechanic is highly recommended especially if it’s a drivability issue. The mechanic can give you his thoughts when you do the test drive before with him and you can validate and check for yourself if the issue is fixed after. In certain cases, ask for codes

The mechanic usually plugs in a scantool in your vehicle’s OBD 2 port under the steering wheel to start the diagnosis. You can look at the Codes that the tool shows which reflects the health of the car and gives us the exact cause of the issue. The mechanic should be able to explain or show documentation on what exactly causes the codes to come up and how to fix them so you are aware of the exact issue yourself.

If you would like to read the diagnostic codes yourself, then you might want to buy an OBD2 Scanner. You can read buying guide and review to find the best one here: https://obdstation.com/. Check them out.

We at FixMyCar always advise our customers to ask as many questions as possible to understand the issue and how to take further care of your car so you won't need us in the future!