Most vehicles have ignition systems and a throttle bore. The vehicle'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 or truck then purchase the appropriate parts to
complete the job.
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)
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
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
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, drive belts etc). Clean and inspect the spark
plug wire separators for reinstallation.
Step 5 - Remove 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
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 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
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 1995 Saturn SL1. Most gasoline powered cars and trucks are similar.
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.
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).
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.
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.
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.
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. We
recommend top quality oil filters and motor oils for your car or truck.
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