When you turn the key in the ignition, you want to see
all the little lights on the dashboard turn off. What if one light doesn't?
When the Check Engine light
won't go out (usually yellow and a funny shape meant to be the outline of an
engine when viewed side-on), you know that something's wrong. You do need to
get to the bottom of it. It could be something as simple as a gas tank cap that
you've forgotten to screw on properly, or it could mean something far more
serious. The bottom line is, when that light comes on, you want to
know what it is.
You could find a mechanic who will diagnose it
Garages charge about £40 in general to diagnose the
cause of a check-engine light that stays lit. For about half the money, you
could buy a car diagnostic engine fault code scanner that gives you in-depth
information on what exactly goes on with your car. It's a handy tool to have
around, even if you don't plan to actually do any repairs yourself. It can give
you information that allows you to have an informed conversation with the
mechanic when you visit the garage.
When you have one of these scanners that tells you
what the problem probably is, it can make it far easier for you to find a good,
honest and reliable mechanic. You can go to a car repair quote generator like whocanfixmycar.com, put in information about the repair that
your code scanner indicates, and simply turn to the garage with the lowest
quote.
Here's a list of the most common errors indicated by a
check engine light.
The oxygen sensor could be faulty
Most cars have four oxygen sensors in the exhaust
line. It is their job to scan the exhaust passing through for oxygen content.
If there's any oxygen there, it means that the engine isn't burning fuel
efficiently and is causing wastage. In most cases, though, it only means that
the oxygen sensors are dead, feeding bad information to the car's computer.
While you could safely let it be in the short-term, you do need to eventually
replace them. If you don't, you could end up damaging the catalytic converter,
which is an expensive component.
The good news is that changing out the sensor is a DIY
task. If you're up to it, your manual will tell you how.
The catalytic converter is faulty
The check engine light could also come on for reasons
of a faulty catalytic converter, a component on the exhaust line that helps
neutralize harmful substances in the exhaust. While it's an expensive part to
replace, you probably want to get to it right away. If it's faulty, the car's
computer will limit your speed, and you'll also notice poor gas mileage. You'll
need an expert mechanic for this job.
The mass airflow sensor could be bad
The airflow sensor measures the amount of air passing
into the engine, and gives the car's computer important information about the
kind of fuel mixture to aim for. An airflow sensor costs £200 or so to replace.
If you want to prevent damage to this sensor, you'll need to make sure that you
get your engine's air filter replaced on a regular basis.
The spark plugs could be old and worn
If your car runs on petrol, the engine in your car
ignites the fuel-air mixture through precisely timed sparks from spark plugs.
If your spark plugs are dirty or worn, you'll need to replace them. Older spark
plugs tend to be rated for 25,000 miles, and newer ones for four times as long.
Nevertheless, if your car seems to not accelerate smoothly, or if it idles in a
noisy way, you could have a problem with the spark plugs. The engine code
scanner should tell you. Spark plugs are easy to replace if you are up to it.
There are all kinds of other faults that the check
engine light could indicate. In general, a steady light is less serious than a
flashing one. If your check engine light is flashing, you want to quickly beat
a path to a mechanic. It usually indicates severe cylinder misfiring.
Finlay Baldwin works as a mechanic, and is a bit
of a car-aholic! When not working on one, he enjoys racing them on weekends,
and writing about them on the odd evening in his spare time.
