Auto Repair Chandler: Under The Hood – More Than Meets The Eye
When the oil gets low, we pop the hood, look for the small yellow cap, and pour in the quart. But do we ever look at the rest of what’s going on under the hood? If we venture a little farther than the oil cap, we might understand that the battery helps start the car. We might discover that the alternator recharges the battery while the car is running.
We might fundamentally grasp that the transmission makes the gears switch. But, we’re literally dancing around the main question: what about that big engine right in the middle?
The average American understands that by feeding the engine gasoline, it makes the wheels turn, but beyond that we get lost. In an effort to get rid of ignorance, below is a step-by-step description of how a standard engine works. Most engines in cars–diesels ignored–are four-stroke engines. This means that for every power stroke that the engine puts out, there are four strokes total that each of its pistons performs. A stroke is when the piston moves from one end of the cylinder to the other, either up or down. In a four cylinder engine, there are four pistons, each performing four strokes per power stroke. The first stroke of the piston is often called the intake stroke because the piston goes to its downward position, allowing a maximum amount of room in the cylinder. Simultaneously, the inlet valve opens and allows a mixture of the car’s gasoline and air to enter the cylinder. The inlet valve then closes, trapping the vaporized fuel inside the cylinder. The second stroke is known as the compression stroke. The piston goes from its full downward position to its full upward position. Because both the intake valve and the exhaust valve remain closed during this stroke, this movement causes the trapped fuel to compress and increase in pressure, temperature, and density. The fuel is now primed to create power. The third stroke is the power stroke. When the fuel is completely pressurized, a small spark is created which ignites the fuel and causes a controlled explosion. The power from the explosion causes several things to happen. First, power is transmitted to the crank shaft which turns the wheels. Secondly, it propels the piston downward and on to the fourth stroke with sufficient power to make it make through the cycle to the next power stroke. Thus, an engine with a consistent supply of gasoline and air is basically a self-sustaining machine. The fourth stroke is called the exhaust stroke. The exhaust valve opens as the piston moves, once again, from its downward position to its upward position. The gas left over from the explosion is forced out through the tailpipe, and the cylinder is once again ready to receive fuel during its next stroke, the intake stroke. The internal combustion engine revolutionized the way man did hundreds if not thousands of tasks, not the least of which is providing propulsion for the automobile. The next time you’re adding oil, pause to appreciate the engine. And don’t forget to schedule time to change the oil and tune up that engine to keep it healthy! Call us today:
TPMS, or Tire Pressure Monitoring Systems, alert you if you have unsafe air pressure in any of your tires. These monitors are installed in your wheels, and alert you through a symbol on the dashboard that looks a little like a flat tire. In 2007, the Federal TREAD act (or Transportation Recall Enhancement, Accountability and Documentation) began requiring all new cars and light trucks come equipped with TPMS. This legislation, like that requiring air bags, helps to keep you safe on the road.
There are so many new and exciting cars scheduled to drop in 2014 it’s hard to know where to start. Why don’t we start by overshooting our own defined time frame and have a look at the 2015 Ford Mustang? In this video, Angus MacKenzie and Ed Loh meet up with Raj Nair (Ford’s Head of Product), Joe Hinrichs (Ford EVP and President of the America’s), and Joel Piaskowski (Ford’s Design Director) to chat about the all-new 2015 Ford Mustang. The guys chat about the Mustang’s radical new look and advanced underpinnings including an all-new high output Ecoboost turbo 4-cylinder!