You should use Top
"What brand or grade of Gas should I put in my
car?" or "My car is running rough at idle, maybe it
needs a tune up." I am confronted with these
Your car runs on gasoline, the
manufacturer and its engineers specifies what grade
and minimum octane rating of your car. Your car was
engineered and programmed accordingly. Not all
gasoline are the same. You get what you pay for
A penny saved at the gas
station will cost you ten dollars at the repair shop
Since the minimum additive performance
standards were first established by EPA in 1995,
most gasoline marketers have actually reduced the
concentration level of detergent additive in their
gasoline by up to 50%, leading to carbon deposits
on fuel injectors, intake valves, and combustion
chambers, which can
have a big impact on in-use emissions and driver
retailers provide fuels with lower-quality additive
packages that can build up deposits on fuel
injectors and on intake valves.
When deposit control additives are not adequate
in gasoline, harmful deposits can build up inside
* Fuel varnish deposits that form inside the
injectors restrict fuel delivery and cause the
engine to run lean. This may cause lean misfire,
rough idle, hesitation, poor fuel economy and
increased HC emissions. A lean fuel mixture also
increases the risk of detonation and pre ignition.
These deposits tend to form during the heat soak
period that occurs after the engine is shut off. The
shorter the trips and the more frequent the drive
cycles, the faster these deposits buildup.
* Deposits that form in the throttle body can
reduce airflow through the idle bypass circuit
affecting idle quality and smoothness. These
deposits are formed by fuel vapors that rise up
through the intake manifold.
Intake valve deposits from gasoline that does not contain enough
* Deposits that form on the intake valves can
restrict airflow through the intake ports, causing a
loss of high speed power. The deposits can also act
like a sponge and momentarily soak up fuel spray
from the injectors. This disrupts the mixing of air
and fuel causing a lean fuel condition, hesitation
and reduced performance. Deposits can also cause
valve sticking and valve burning. Intake valve
deposits are formed by normal combustion byproducts,
but may build up more rapidly if the valve guides or
seals are worn and the engine is sucking oil down
* Deposits that form inside the combustion
chamber and on top of the pistons increases the
compression ratio of the engine and the octane
requirements of the fuel. Too much compression can
cause spark knock (detonation) if the fuel's octane
rating isn't high enough. Over time, detonation can
damage the head gasket, piston rings and rod
bearings if it is not controlled. The knock sensor
will detect detonation and tell the computer to
retard spark timing. This will take care of the
knock, but retarded timing also increases fuel
consumption and emissions.
A build up of carbon deposits inside the
combustion chamber also increases the risk of hot
spots forming that may cause engine-damaging pre
ignition. The hot spot ignites the fuel before the
spark plug fires, causing a sharp rise in combustion
pressure. Under extreme conditions (high rpm and
load), pre ignition can burn a hole right through
the top of a piston!
Six of the world's
top automakers, BMW, General Motors, Honda, Toyota,
Volkswagen and Audi recognize that the current EPA
minimum detergent requirements do not go far enough
to ensure optimal engine performance. They developed
a TOP TIER Gasoline standard requirement.
These automakers have
raised the bar. TOP TIER
Detergent Gasoline help drivers avoid lower quality
gasoline which can leave deposits on critical engine
parts, which reduces engine performance. Thatís
something both drivers and automakers want to avoid.
manufacturers have issued special service bulletins
advising their dealers of this issue.
Just remember, you will
spend at the repair shop a lot more than what you
are saving at an inexpensive gasoline station.
known to be on the TOP TIER list are shown below.
MFA Oil Co.
The Somerset Refinery, Inc.
Kwik Trip / Kwik Star
Tri-Par Oil Co.
Turkey Hill Minit Markets