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The Ignition System

To get the fuel air mixture burning, the ignition system ignites the flammable mixture by firing a powerful electrical spark across the electrodes of the spark plug. The engine. s ECU controls the timing of this spark. The spark is fired as the piston has almost risen to Top dead Center (TDC) near the peak of the cylinders highest compression. This is the most efficient time to fire the spark. Usually the timing of the spark advances as the engines RPM increases. This is because at higher RPM there is less time for the combustion event to take place so it must be started sooner in the cycle to maintain proper operation.

The Exhaust System

The exhaust system is simply the tubing that directs burned exhaust gases away from the motor. The exhaust system consists of the exhaust manifold, the catalytic converter and the exhaust pipe. The manifold collects the exhaust gas from each individual exhaust ports in the cylinder head and collects them into a single pipe. This pipe leads into the catalytic converter where poisonous constituents of the exhaust gas such as Oxides of Nitrogen (NOX), various unburned hydrocarbons (HC) and carbon monoxide are converted to non-toxic CO2 and water vapor. After the catalytic converter, the gases flow into the exhaust pipe where they pass through the muffler, which reduces the noise to an acceptable level and out into the atmosphere.

Although not directly responsible for motivating your ride but nevertheless deserving an honorable mention as critical parts of a motor is the engine’s cooling and lubricating systems.

The cooling system circulates a mixture of antifreeze and water throughout the block and head keeping them from getting too hot from the continuous explosions that they are subjected to internally. The water is pumped out of the block to the radiator, which is a heat exchanger located in the very front of the car, to be cooled down and re-circulated back through the engine. A faulty cooling system can wreck a motor very quickly by letting it overheat. Although this sounds very basic, my neighbor almost ruined his motor by driving around for several days with his temperature gauge pegged, when his radiator sprung a leak. He really did not know that overheating will surely destroy an engine very quickly. The fact that his Integra still runs pretty well once he fixed the radiator is a strong testament to the bulletproofness of these engines.

The lubrication system consists of a pump which pumps oil to all of the engines bearings located on the crank, and the valvetrain. The pistons and rod wristpins usually rely on splash that is created as oil is flung off the rotating crank. One of the quickest ways to ruin an engine is to run it out of oil. My neighbors older brother almost trashed his Acura Legend’s engine by doing this once. He did not realize that periodically you must check the oil level, and nearly ran the engines oil supply down to nothing. Fortunately he asked me what the oil pressure warning light meant, and we caught the low oil level before any damage was done. Don. t laugh, the only reason that I, a supposed expert, know this stuff is that it was drilled into my head by my engineer father. My neighbors father owns a restaurant and does not work on his car at all. He doesn’t work on cars and my Dad cannot cook awesome Chinese food.

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