Over time and miles, your car might start to slow down. It might not accelerate as quickly as it once did; the engine may not run as smoothly as you remember, or the fuel economy may dip—but ...

In order for a petrol engine to run at its most efficient, fuel must be metered into it in precise amounts. If it is supplied with too much fuel then it will run 'rich', causing excessive fuel ...

Over time and miles, your car might start to slow down. It might not accelerate as quickly as it once did; the engine may not run as smoothly as you remember, or the fuel economy may dip—but ...