Most vehicles have ignition systems and a throttle bore. The
enigne's ignition system
is the component that ignites the fuel air mixture inside the combustion chamber.
When an ignition system fails, it can cause various symptoms such as
stalling,
rough engine under power,
service engine light (check engine) and complete engine shut down. Be sure to
keep your vehicle's engine and fuel system clean to assure the proper operation
of your vehicle. The step by step instruction below is characteristic of today's
ignition and air intake systems. Most vehicles today need a tune up every 35,000
to 65,000 miles depending on driving conditions. Before starting determine which
tune up parts are needed. Inspect the particular system on your car then purchase
the appropriate parts to complete the job.
Step 1 - Identify Throttle Bore (air intake plate and bore)
Cleaned Throttle Body
Most vehicles have an air intake system that will become clogged with air contaminants
that the air filter cannot
keep out of the system. This condition is called "coking" and can cause stalling
as well as variable idle condition and poor mileage. The throttle bore in this illustration
has been cleaned for visual purposes. Usually the throttle bore and plate are coated
with a dark light tar that needs to be cleaned with every tune up.
Step 2 - Cleaning the Throttle Bore and Throttle Plate (air intake plate
and bore)
Opening Throttle bore
Most vehicles have a throttle cable that can be held open to help with the cleaning
procedure. Open the throttle bore and with a cleaning towel and cleaner, (rubbing
alcohol works well) continue cleaning until the throttle bore and plate are clean.
Step 3 - Identify Tune Up Components
Identify Ignition Components
Most vehicles have two kinds of ignition systems. The first is DIS (distributor
less ignition system) and COS (coil over spark plug) no spark plug wires. If you
can't identify which system you have, follow this link to get the right system for
your car (car repair
manuals). Confirm your vehicle to determine the tune up parts needed. A typical
tune up includes spark plugs, air filter,
fuel filter, spark plug wires,
distributor cap and ignition rotor. You must determine which parts are needed before
you start.
Step 4 - Remove Plug Wire Retainer Guide
Plug Wire Retainer
Remove the spark plug wires retainer clip(s). These are important in keeping
the plug wires separated and controlled to avoid any contact with undesirable components
(exhaust manifold, serpentine belts etc). Clean and inspect the spark plug wire
separators for reinstallation.
Step 5 - Remove Plug Wires
Removing Plug Wires
Remove the spark plug boot end and twist the boot to break the airtight seal
created round the plug wire boot. Then gently pull the spark plug wire from the
spark plug. Remove the plug wire from the coil terminal. It is important to change
the spark plugs and wires ONE AT A TIME to make sure you don't get the wires mixed
up. If you have already taken them all off at once and cannot get them back on correctly,
visit this link for the proper engine firing order,
car repair manuals.
Step 6 - Matching to Replace Plug Wires
Comparing Plug Wire Length
Remove all plug wires from the packaging, straighten them out and organize the
plug wires from largest to shortest. Match up spark plug wires by length and reinstall
one at a time.
Step 7 - Remove Spark Plugs
Socket Wrench Removing Spark Plug
Next, remove debris from the spark
plug hole, (canned air works best) then use a socket wrench and spark plug socket
to loosen and remove spark plug (counter clockwise). Inspect spark plug for damage.
Step 8 - Replace Spark Plug
Measuring Spark Plug Gap
Remove the spark plug from the box or container and inspect the new plug for
damage that could have occurred in shipping. A spark plug has a porcelain isolator
that is fragile and can crack easily. Next inspect the spark plug gap using a spark
plug gap checker. The "air gap" should be measured as per manufacturer specifications.
Most plug gaps are between .035 and .045 thousands of an inch. This gap is important
because it determines the amount of resistance used to "time" the system. An incorrect
spark plug gap will result in poor running,
low power, poor mileage and
a check engine light notice. Reinstall the spark plug and install the new spark
plug wire. Most of the time a spark plug will come "pre-set" and ready to install.
Continue the process until all spark plugs and spark plug wires have been replaced.
Be sure to use OE (original equipment) parts for your car to insure the proper performance
from your vehicle. This tutorial has outlined a tune up on a gasoline power engine,
four cylinder. Most gasoline powered cars are similar.
Required Tune Up Parts
Before starting determine which tune up parts are needed. Inspect the particular
system on your car or truck then purchase the appropriate parts to complete the
job.
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Spark Plugs - A spark plug will last between 20,000
and 60,000 miles depending on the style of spark plug that is required by
your specific vehicle. The spark plug is the firing point in which the electricity
is passed through a gap to ignite the fuel/air mixture inside the engine
(combustion chamber). |
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Spark Plug Wires - Spark plug wires need to be changed
every time a tune up is performed. With today's ignition systems, the running
voltage and amperage is higher than ever; even more reason to service your
spark plugs wires before they burn out and cause a misfire. |
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Ignition Rotor - An ignition rotor is used to relay
the electrical spark from the ignition coil to the terminals on the distributor
cap and then onto the sparkplug wires and eventually to the spark plugs.
Some cars and trucks do not use an ignition rotor so inspect your vehicle
before you start. |
|
Fuel Filter - Fuel filters will last up to 25,000 miles
or more depending on the type of driving you do. If you live in a dusty
area like the desert or if there is extreme moister in your area, you can
expect to change your fuel, oil and air filter more often. Make sure to
replace your fuel filter at regular intervals to insure the safety of your
vehicles fuel injection system. |
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Distributor Cap - A distributor cap is the component
that allows the ignition spark from the ignition coil and separates it into
the individual spark plugs as it rotates inside the ignition distributor.
Some cars and trucks do not use an ignition rotor so inspect your vehicle
before you start. |
|
Air Filter - Air filters will last up to 3,000 miles
or more depending on the type of driving you do. If you live in a dusty
area like the desert or if there is extreme moister you can expect to change
your oil and oil filter's more often. Make sure to inspect your oil level
at regular intervals to insure the safety of the internal parts system of
your vehicle. To inspect or change your air filter follow the instructions
above.
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Oil Filter - Oil filters will last up to 3,000 miles
or more depending on the type of driving you do. Different oil types, like
synthetic, give you more mileage between services. If you don't know when
the last oil change was on your vehicle and would like to determine where
you stand, remove the oil level inductor and check the clarity of the oil.
If it is light colored like tea, you are ok. If it is dark like Cola, it
is time for service. |
If further assistance is needed, our certified car repair technicians are ready
to answer your car questions.
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