Why does my engine light come on periodically?

Why does my engine light come on periodically?

But, there are other possible causes of intermittent illumination of the Check Engine Light such as failures in engine sensors, intermittent misfires, and faults with sticky or stuck valves such as in the EGR (exhaust gas recirculation) system or the EVAP system.

Why does my engine light keep going on and off?

Worn-out spark plugs can affect your engine’s combustion process and throw it all out of whack. It can also lead to a check engine light on and off intermittently. The thing about bad spark plugs is that, initially at least, you’re going to be able to continue to drive around with them.

Is it possible to reset an engine warning light?

While the documentation for some older cars provided instructions on how to check and reset engine warning lights, it’s not usually possible now cars have grown more sophisticated. It’s well worth paying for accurate diagnosis, though, so a proper and effective repair can be made.

Do you need an engine warning light to pass Mot?

The answer to this is ‘no’ – the light itself isn’t but the issue that causes could prevent your car passing its MoT depending on what it is. Unlike many of a dashboard’s other warning lights, an engine warning light doesn’t alert you to a specific fault.

Why is there a warning light on my diesel engine?

Some diesel-powered cars have a specific warning light for their diesel particulate filter (DPF), whereas others don’t and rely on the EML providing a warning instead. The latter is sometimes also illuminated if the car detects a fault with the differential pressure sensor, which determines how effectively the DPF is performing.

When to worry about Intermittent check engine light?

Typically an intermittent check engine light concern happens under very specific conditions such as when it’s hot, cold, damp or driving over bumps. Knowing this information can greatly reduce the time it takes to locate the source of the fault. The first thing we need to do is duplicate the concern.