1. piston
   spark plug
2. distributor cap
   lighter

The whole point of your spark plug is to convert electricity from the battery or alternator into a spark inside the cylinder, igniting the fuel and oxygen to force the piston downward.

1. pulley
   oil cap
2. valve cover
   sump cover

The oil cap is one of the simplest and most overlooked engine parts out there. Without it, you couldn't quickly and easily add oil to the engine. Just remember to put it back when you're done.

1. engine cover
   timing belt cover
2. engine mount
   cylinder block

Engine mounts ensure the engine and transmission stay in place all the time, but they also help isolate excessive vibrations, otherwise the entire car would shake constantly.

1. cylinder
   cylinder head
2. camshaft
   catalytic converter

Once the air and fuel are in the cylinder, the valves have all closed and the piston has finished compressing the gas mixture, it's time for combustion via the spark plug. This magic should be contained to the cylinder.

1. driveshaft
   transmission
2. crankshaft
   axle

The movement of the pistons is transferred into a spinning motion at the crankshaft, which is the type of energy that's ultimately sent to the car's wheels so you move.

1. cylinder inlet
   flow port
2. magic portal
   intake valve

The intake valve will move down into the cylinder, allowing the waiting air and fuel mixture to flow in, before it pulls back up and seals off the combustion chamber.

1. do-hickey
   escutcheon
2. pushrod
   connecting rod

Connecting rods are incredible strong and durable, which they have to be, considering they're subjected to some powerful forces constantly. Damage to a connecting rod means you're looking at an engine rebuild.

1. cylinder head
   catalytic converter
2. O2 sensor
   intake housing

The cylinder head controls how the different gases flow into and out of the combustion chamber. An engine might have two cylinder heads, depending on its configuration.

1. camshaft position sensor
   spark sensor
2. knock sensor
   timing sensor

Really bad cases of engine knock are easy to hear, but this sensor can detect knock that you wouldn't notice otherwise, catching the problem so the ECU can retard timing to compensate.

1. oil sump
   oil pump
2. oil river
   oil lake

The sump is the lower portion of the engine where the oil collects by sheer gravity. Of course, the pump is responsible for sending the oil where it needs to go.

1. rocker arm
   intake manifold
2. piston
   air intake

The piston performs a few vital functions in your engine, including compressing the air/fuel mixture before it combusts, and transferring that energy into downward motion.

1. exhaust finisher
   muffler
2. exhaust manifold
   turbocharger

The exhaust manifold bolts right onto the engine, and has the sole purpose of giving the exiting exhaust gases somewhere to go, otherwise they'd gather in the engine compartment.

1. oxygen thing
   O2 sensor
2. oxygen port
   oxygen meter

The O2 sensor plugs right into the exhaust manifold, which is constructed with a special port for that very purpose. The ECU can adjust the air/fuel mixture depending on feedback from this sensor.

1. fuel injector
   fuel sprayer
2. fuel port
   ignition wire

Fuel injection was a major technological breakthrough back in the day, since it adds a level of precision you don't get with a carburetor.

1. valve lock
   valve spring
2. valve channel
   valve do-hickey

One of the unsung heroes in your engine is the valve spring, which makes achieving proper cylinder compression possible.

1. crank spinner
   centrifugal guide
2. timing belt
   timing bearing

Some engines have timing chains instead of timing belts, which perform the exact same job. A broken chain or belt can cause serious damage in an interference engine.

1. water jacket
   engine cover
2. air intake
   air outlet

The water jacket is a series of passageways that run through the engine, allowing coolant to flow through unobstructed and soak up excess heat. Without it, your engine would literally melt.

1. peanut butter
   engine sealant
2. head gasket
   engine cover

A blown head gasket, or one that doesn't create that tight seal anymore, can cause all kinds of problems for your engine. The only solution is to remove it and install a new one.

1. ignition wire
   breaker
2. electrical fuse
   fuse box

The ignition wires have a long tube which fits into the spark plug wells in the engine. The open end of that tube fits over the end of the spark plug, with an element inside creating an electrical connection.

1. exhaust channel
   exhaust port
2. exhaust stream
   exhaust valve

The movement of the exhaust valve is different from the intake valve, but both stay shut tight during compression and combustion, otherwise your engine won't run smoothly or perform optimally.

1. crankshaft
   timing differential
2. timing stick
   camshaft

Some cylinder heads have a single camshaft, while others use two, one for the exhaust valves and one for the intake valves.

1. peanut butter
   intake manifold gasket
2. intake sealant
   intake weld

Just like all other parts that bolt to the engine, the intake manifold must have a gasket to create a genuinely airtight seal. Replacing a blown gasket is fairly simple.

1. flywheel
   clutch
2. transmission interface
   potters wheel

The flywheel is heavy and is designed to always be spinning at a smooth rate. Your engine doesn't provide smooth power delivery, so the flywheel makes up for that inconsistency when transferring energy to the clutch and transmission.

1. valve actuator
   pushrod
2. valve control module
   valve thingy

Because the camshaft in an overhead valve engine isn't located in the cylinder head but the valves are, pushrods are necessary to transfer the camshaft movements to the valves.

1. thermometer
   air temperature sensor
2. ambient modulator
   engine thing

The air temperature sensor communicates with the ECU, which will adjust the air/fuel mixture. The colder the air, the more oxygen molecules are contained in a cubic inch, which is better for performance.

1. pull pin
   bull pin
2. small connecting rod
   gudgeon pin

It may be small, but the gudgeon pin performs a big job. It's subjected to tremendous forces constantly, meaning this little component is one tough cookie.

1. oil level sensor
   oil sump meter
2. oil pressure sensor
   oil sending unit

The oil pressure sensor performs an absolutely vital function for your engine, because without it you could run the engine dry, causing different parts to seize.

1. fuel rail
   fuel pump
2. fuel sending unit
   fuel module

The fuel rail subjects the fuel to an incredible amount of pressure, which is necessary before its sent to each of the injectors in turn.

1. timing housing
   bell housing
2. timing belt cover
   belt storage module

Before you can even inspect your engine's timing belt, you have to remove this cover. Hopefully that's an easy process, but that's not always the case.

1. camshaft modulator
   timing pulley
2. cam cap
   cam rotisserie

Both the timing belt and the timing pulley have teeth that intermesh with each other, that way the belt won't slip off the pulley, unless the belt is damaged or worn out.

1. oil level gauge
   oil level indicator
2. oil dipstick
   oil modulator

Using an oil dipstick is a simple process, but you need to clean it off and then reinsert it into the tube for an accurate reading.

1. valve clearance modulator
   valve gapper
2. valve grip
   valve lifter

Valve lifters that are hydraulic don't require adjustments on a regular basis, so they're much lower maintenance. It's the conventional or solid lifters that require you to stay on top of regular adjustments.

1. oil sump
   oil pump
2. oil dump
   oil drumpf

Oil naturally flows down, thanks to gravity, collecting in the sump. The oil pump will send the oil to the various parts of the engine, ensuring everything is lubricated properly, avoiding engine failure.

1. exhaust manifold gasket
   exhaust seal
2. peanut butter
   exhaust jelly

Like the other gaskets on the engine, this one is used to create an airtight seal. Without it, the exhaust gases could collect under the hood of the car, which is a dangerous situation for everyone in the cabin.

1. short pushrod
   engine valve controls
2. rocker arm
   oscillating valves

Whether the rocker arms are pushed up or down by the camshaft lobes, the purpose is to actuate the valves, ensuring the flow of intake mixture and exhaust gases happens exactly when it should.