Pep Boys Auto Guide to Car Care and Maintenance (eBook)

A Tutorial of Your Car and How It WorksLearning How to Drive Sure, you know how to put the key in, shift into drive, and pull away-but do you really know exactly what goes on inside the car when you're out there on the road? You will by the end of this section! When you're done, you'll no longer think of your car as a Big Black Box, but as a logical sum of its fairly simple to understand parts. Note: If you find this next part confusing or the terminology a little alien at first, don't worry. Continue to read through the next section on all the different systems in your car-and we'll go through all of this again. It will make sense-we promise. When you put your key into the ignition and turn it, you close a switch that allows electricity to flow from the battery to the starter, an electric motor that starts turning the crankshaft. As the engine spins, the pistons and the fuel start pumping and the valves start opening and closing. Compression is achieved, the spark plugs fire, and the engine itself takes over. The starter then disengages itself from the process. The fuel pump delivers gas to the cylinders of the engine through intake valves, where it is mixed with air and compressed by the pistons. This highly combustible mixture is lit by the spark plugs and explodes, forcing the pistons down, which then turns the crankshaft. The crankshaft connects to the transmission, which determines with how much power and at what speed the wheels should turn. To shift gears, the car must first release the transmission from the crankshaft, and this is done by a clutch if it's a car with a manual shift. Power is converted hydraulically through a torque converter in an automatic, transferring engine power by the use of fluid. In rear-wheel-drive vehicles, the driveshaft continues from the transmission on to the rear of the car, with a hinge on each end called a universal joint (or a CV joint in a front-wheel-drive car) to keep the whole thing flexible and from snapping like a twig when the car hits a bump. A differential (sometimes called a rear end) at the end of the driveshaft delivers the turning power of the shaft and converts the power through a ring and pinion gears 'sideways' to the two rear wheels and determines the difference in speed that each wheel must have in order for you to execute a turn. When turning, the outside wheel must turn faster than the inside wheel or you would break the axles or gears. The differential is what allows this to happen. In front-wheel-drive cars there is a transaxle instead of a transmission, which handles gear-shifting as well as the individual speed of the left and right front tires for when you want to turn. Oil keeps everything lubricated and operating quietly and properly. . . . Now, that wasn't so hard, was it? Okay, it was. So now let's break down your car system by system and go through each one simply and clearly. We'll put it all together at the end of this section again-and you'll be amazed by how much you've already learned. Breakdown: Your Car, System by System Engine Okay. This is actually a far simpler thing than you might imagine. Relax, take a deep breath and imagine yourself in a tropical paradise . . . on a bicycle. In the same way that bicycle pedals go up and down, the crankshaft in a car pumps up and down, transferring rotation and power to the wheels. But instead of legs (and feet), a car engine has pistons that push down on the crankshaft. The pistons are propelled downward by an explosion above them in the cylinder. So the more cylinders you have, the more pistons you have,...