Engine deposits caused by low-quality or contaminated gasoline create drivability problems, and the cure for that might be a fuel system cleaning, either by a repair shop or with a gas-tank additive. An illuminated check engine light signals when something is amiss in the emissions control system, but depending on what the issue is it could also affect fuel economy or engine performance, so don’t ignore it. A faulty oxygen sensor, for example, leaves the engine computer in the dark about how to set the air-fuel mixture, and that can result in poor fuel economy.
A dirty or clogged engine air filter is more likely to reduce acceleration than fuel economy, according to tests conducted by the EPA. Because filters get dirty gradually over time, you might not notice a small but steady loss of performance until your car is accelerating like a turtle. But if you haven’t changed the filter in a couple of years (or sooner in areas that have a lot of soot in the air), that could be part of the problem.
If the battery light is on and you're still driving the car, turn off as many electrical accessories as you can, such as the stereo, air conditioning or heater, and avoid using electrical controls such as power windows. Reducing the amount of electricity the car is consuming will increase the distance you can drive before the battery is discharged. Get to a mechanic as quickly as possible, and have the battery, wires and charging system checked out to find the cause of your problem and what you need to repair or replace.
Modern cars come with complex electrical systems meaning that electrical diagnostics tools are needed in the repair and maintenance. That being said, the following are some of the most common auto diagnostic tools you will find in most auto electric repair shops. Digital motor checker - This is a vehicle diagnostic tool used in the maintenance of inbuilt electrical systems without any dismantling having to be done. This device helps in detecting problems that may result in tripping and therefore compromised electrics.