Repair 7

The spark plug is a vital component in the operation of an internal combustion engine. As the name implies, the spark plug creates a spark that ignites gasoline inside a combustion chamber. This creates the energy to force the piston downward. The movement of the pistons gives the engine its power. To make sure that the engine operates as smoothly and efficiently as possible, it needs to be tuned up on a regular basis. An important part of that tune-up is removing and replacing the spark plugs, a process thats fairly straightforward.

Instructions

1

Make sure the engine is cool. The spark plugs are one of the hottest components of an engine.

2

Clean any dirt or debris from around the base of the plug to keep dirt from falling into the combustion chamber. Use compressed air to blow debris away if it is available.

3

Use your owners manual to find the spark plugs. Most engines have spark plugs wires that lead to the spark plugs. Newer engines may have individual ignition coils mounted over the spark plugs.

4

Remove the spark plug wire from the spark plug by pulling on the rubber boot. Do not pull on the wire itself. If equipped with ignition coils, remove the ignition coil mounting bolt to remove the coil and reveal the spark plug.

5

Install the spark plug socket on the socket wrench. You may need to use a swivel joint or a socket wrench extension to reach spark plugs in the back of the engine.

6

Place the socket over the spark plug and turn the socket wrench counterclockwise to loosen the spark plug. Use steady force to remove a stubborn plug. Too much force can shear off the top of a spark plug or strip the threads.

7

Continue to turn the wrench until the spark plug comes out of the hole. Once loosened, you should be able to remove it by hand.

When a vehicle engine is reluctant to start, it often means that the spark plugs need changing. Like many automotive components, spark plugs dont last forever. A common malfunction is a wet spark plug. According to AA1Car.com, this occurs when the spark plug fails to fire, or fouls out. This can be caused by a number of variables, such as engine flooding, or excessive moisture build up.

Engine Flooding

Failed vehicle starting attempts eventually lead to wet spark plugs, according to E3 Spark Plugs. This happens when drivers attempt to start their vehicles multiple times without success. This can lead to engine flooding, which in turn can soak the plugs so theyre unable to form any kind of spark to start the engine. This often happens in cold weather conditions, when spark plugs that are previously worn or fouled require a higher voltage to ignite the engine. In this case, the best thing a driver can do is either wait for the plugs to dry, or remove the plugs and clean them off.

Injector Leaks

Wet fouling is less common on modern fuel-injected engines, but can happen due to a number of mechanical failures, states AA1Car.com. One example is a leaking cold start injector. This would lead to the creation of a rich start up mixture in the engine compartment that would cause the plugs to foul.

Worn Piston Rings

In older vehicle engines, worn piston rings or excessive cylinder wear often lead to wet fouling, states Mopar Magazine. This could result in the release of excess oil or gasoline into the engine compartment, which could prevent a spark from forming during an ignition attempt. Wet-fouled spark plugs can be cleaned and re-installed to work effectively.

Replacing the spark plug wires with a new set of high-quality wires on your Toyota Camry can improve the performance and allow the engine to run smoother. New plug wires can increase the fuel economy of the car as well. Regular inspection of the wires for cracks, nicks, tears or burns is the best way to know when the wires need to replaced. Spark plug wire sets are available from Toyota dealers and most auto parts stores.

Instructions

1

Open the hood of your Camry and locate the negative cable on the battery terminal. Remove the retaining bolt from the battery cable end with a wrench. Lift the cable off the battery. Set it aside, making sure it cannot fall back against the terminals while you are working.

2

Locate the spark plug wires on the top of the engine. The wires run from the ignition coil or coil packs to the spark plugs. There are four on the 2.2-liter engine and six on the 3.0-liter engine.

3

Pick one wire. Remove the wire from the coil by pulling the wire off the terminal. Follow the wire to the spark plug. Grasp the wire by the boot on the spark plug end and pull it off the spark plug.

4

Lay the spark plug wire out straight and find the matching wire from the new spark plug wire kit. Place a small amount of dielectric grease in each end of the wire. Install the new wire on the coil and the spark plug. Push the wire onto the terminal and the plug until it snaps in place.

5

Move to the next wire and repeat the process. Continue replacing plug wires until all of them are new. Do not remove more than one wire at a time. Doing so could affect the firing order, in which case the engine will not run correctly.

6

Reattach the negative cable on the negative battery terminal. Tighten the retaining bolt with a wrench. Close the hood and discard the old wires.

Some roads are paved with good intentions, others with broken dreams; still others are paved with broken down cars, formerly driven by people with good intentions. Lubricating spark plug threads is one of those things that seems like a good idea at the time, until you realize all the reasons that you shouldnt do it.

Spark Plug Basics

A spark plug is, in essence, the end and the weakest link in a long circuit. The electrons flowing across the gap from the spark plug tip to the ground strap start at the battery. Electrons flow from the battery, and through the ignition coil where they induce a high-voltage/low-amperage in a metal core. The high-voltage electricity flows through that core and into the plug wire -- or spark plug, if its direct ignition -- where it flows down the plugs central, metal core. From there, the electrons jump the gap in the form of a spark to the ground strap, grounded to the battery via the cylinder head and ground strap.

A Case for Lube

Anti-seize lubricants are usually some mixture of soft metals with high lubricity -- copper and aluminum, typically. They also generally contain some amount of graphite, which acts as a "dry" lubricant and helps to keep bolt threads from sticking to the threads of a bolt hole. Antiseize lubricants do their best work on bolts in high-temperature, mixed-media applications -- steel bolts into aluminum heads, chrome-moly exhaust manifold bolts into iron heads and so on. Anti-seize lubes can go a long way toward the prevention of stuck bolts, stripped threads, stripped bolt heads and broken spark plugs.

Electrical Conductivity

Contrary to popular belief, most anti-seize lubricants are fairly good conductors of electricity -- they just need to get hot to do it. Aluminum and copper are two of the best electrical conductors on Earth, and graphite is a fine conductor as well. But, unlike most materials, this crystalline form of coal has whats called a "negative coefficient of resistance," meaning that it works better when its hot. Very hot -- about 900 degrees Fahrenheit. So your ignition system wont work very well at startup or unless the engine runs consistently at very high temperatures. Thats why its often proscribed for use in aircraft engines, which require regular maintenance and run at high loads for hours at a time.

Galled Threads

Not all antiseize compounds contain graphite; some specialized compounds designed for use with electrical components contain nothing but copper, aluminum, nickel and other conductive elements. But that still does change the fact that antiseize lubricants are still lubricants, and that theyll reduce required torque by about 20 percent. Which means that, when you use an antiseize lube and torque the plugs to the factory setting, youre actually over-torquing by about 20 percent. When dealing with aluminum heads, an extra 20 percent is easily enough to rip the threads right out of your head, thus creating the very problem you were trying to avoid.

The engine spark plug, whether used in automotive applications or commercial and industrial use, serves a straightforward purpose. It has the job of sealing off the combustion chamber while generating a high voltage to spark an explosion of atomized fuel and air. Spark plugs come in many heat ranges, sizes and construction materials, which have reference numbers. Two Champion spark plugs, such as the RN9Y and the RN9YC, have similar designs except for an additional identification number.

Spark Plug Description, Letter "R"

The RN9Y Champion spark plug has four reference numbers that describe its specific application. The first letter, "R," describes the special suppressor shielding construction of the plug, which identifies it as a resistor-type plug, used for suppressing radio and engine-noise static. The RN9YC spark plug is no different in this respect.

Letter "N"

The "N" describes the physical construction of the outer shell. In this case, the outer shell has a 14 mm thread size, a 3/4-inch reach, or depth into the combustion chamber and a 13/16-inch hex bolt design. The RN9YC spark plug is the same as the RN9Y in this aspect.

Numeral "9"

Typically, Champion spark plugs that have numeral designations between 1 and 25 have application use in automotive and small engines only. The number "9" falls within this range, excluding it from use in larger commercial and industrial engines. The RN9Y and RN9YC spark plugs are identical in this respect.

Letter "Y"

In a Champion spark plug, the letter "Y" on the RN9Y spark plug refers to the firing-end design of the spark plug electrode. In this case, the "Y" indicates that this spark plug uses a standard projected core nose, one of the most common configurations. Electrode length determines the heat range, and in some cases, the depth of the plug inside the combustion chamber. The "Y" on the RN9YC spark plug means the same thing.

Letter "C"

The extra "C" for the RN9YC spark plug identifies it as a copper-core plug, which makes the core construction material different from the RN9Y spark plug. The electrode center contains an extruded copper core that promotes better heat-range distribution. This allows for longer plug life. The copper electrode element also resists corrosion and contamination better than the standard design. The RN9YC spark plugs have useful applications when used on HEI (high energy ignition) systems that require better quality and longer plug life.