Common Issues

1. Check Engine Light Diagnosis:
   • Why is my check engine light on? Check engine light can illuminate for many different reasons. This is your car’s way to communicate that something has either malfunctioned or had an intermittent failure. This can be a indication of a serious issue that may need attention or it could be a minor problem starting to develop.
   • How to diagnose check engine light codes? Modern vehicle are equipped with an on board diagnostic port. This is where a device may be connected to the car’s computer and a technician can retrieve what is called a fault code. This code is a representation of which component system had the failure. The system would than need to be tested and inspected to locate the source of the failure in order to take the proper corrective action.
   • Common reasons for a check engine light. The most common reason for a check engine light to illuminate is a poor seal on the fuel filler cap. If the cap is not completely secured a loss of pressure is identified by the car’s computer and reports this as a emission system leak. (See Emission System). Another reason would be from a monitoring sensor that has either failed, is beginning to fail or has received poor signal from the system which it is monitoring. In some cases the car would perform with out any problems however excessive fuel consumption may occur and in some rare cases car can enter a limp mode which is design o get you off the road and not intended for street driving as accelerating power would feel limited. And in the most extreme cases is it due to catastrophic failure which will show symptoms in addition to having the check engine light illuminate on the dash. If the check engine light begins to flash that would indicate a much more urgent condition which would require immediate attention to prevent further damage.
   • Engine components and operation: The engines job is to create power to spin the wheels. The internal combustion engine unitizes a chemical charge consisting of air and fuel to compress and ignite the mixture to create combustion which creates reciprocating force and is converted into a rotational mass, thereby spinning the wheels to move the vehicle. Engine components consist of the engine case, cylinders, cylinder head, crankshaft, piston, connecting rod, cam shaft, cam chain or timing belt, valves spark plugs, fuel injectors, starter, along with a group of sensors and a computer. A four stroke engine will send the piston up and and down two times to complete a full cycle. The first stroke is the intake stroke where the pistons downward movement while the intake valve open will suck air and fuel into the cylinder through the cylinder head where the valve is located. The second stroke is the compression stroke which is when the piston travels upward with all valves closed to compress the air and fuel mixture. The third stroke is the combustion stroke this is where the air and fuel mixture is ignited by the spark plug based on very specific timing input from a camshaft or crankshaft position sensor reported through and activated by the computer thereby driving the piston downward creating power which spins the crankshaft which is located in the engine case and has an output shaft into the drivetrain via the transmission. The computer which is also called an ECU (engine control unit) or PCM (power control module) takes reading from the various position sensors to activate fuel delivery and spark distribution. The fourth stroke is the exhaust stroke which utilizes the momentum created by combustion and stored in the crankshaft to drive the piston upward while the exhaust valve which is located in the cylinder head is open to expel the burnt air and fuel mixture. This momentum continues to power the next cycle as the engine enters the intake stoke once again to complete the four stroke cycle again. The speed at which the cycles are being completed is represented by RPM (revolutions per minute). As you accelerate the engines will perform these four cycles faster and faster thereby creating maximum power. When you hit the start button or turn the key to the ignition position, electric power is sent into the starter motor’s solenoid which engages and spins the starter gear that initially turns the crankshaft thereby driving the piston to initiate the compression stroke. Once the engine starts up it will propel itself to complete all four stroke as long as all the appropriate conditions are met, which are the presence of air, fuel, spark and compression, if one of these conditions are not met engine will not run properly.
2. Braking System:
   • Braking system components and operation: Brakes stop the vehicle by pressing the brake pedal. When you apply your brakes a stationary friction pad squeezes onto a disc that spins together with the wheels in order to stop your car. Components consist of a brake pedal, master cylinder, brake lines, brake caliper, brake rotor and brake pads. When pressing on the brake pedal the master cylinder pressurizes hydraulic fluid within the system to engage the brake caliper which houses the brake pads which squeeze the brake discs to which the wheels are directly attached thereby slowing the vehicle down to a stop. Brake pads and rotors are a sacrificial part, designed to wear as they are being used to perform their function. This is one of the most important vehicle functions therefore a safety inspection should be conducted with every service.
   • How to change brake pads and rotors? Brake replacement is a common maintenance to be performed based on the result of a routine safety inspection which should be performed with every oil change service. When brake pads reach crucial measurement that indicates they will not have enough life to reach your next service. When replacing brake pads the brake discs are typically resurfaces in order to prevent vibrations and excessive noise, which can develop if the procedure is not carried out. A small gap may develop between the brake pad and rotor mating surface area which can attract dust and moisture build up to cause bothersome sounds when braking.
   • Brake pedal feels soft, what could be the problem? Braking system is a hydraulic system which uses hydraulic fluid to pressurize the friction pad and disc mechanism to stop the wheel spin. When applying the brake pedal the fluid is pressurized expands a piston which squeezes on the brake pad therefore by pressing the friction material to the disc to stop the wheel. When the fluid level is low the pedal will not feel as firm as it should and would cause you to not have full engagement of the friction material during a panic stop subsequently increase your stopping distance. This can be caused by old fluid that has not been serviced as it does draw moisture from the atmosphere and becomes compressible. It can also be caused by worn pads, or a fluid leak in extreme situations which can lead to brake failure.
   • Signs of brake problems and solutions. The best way to determine if brake pads need to be serviced is by having them routinely inspected during your regular service. A common symptom of work brakes is a metal scraping sound which comes from a metal scraper also know as a wear sensor with will rub on the brake disc when the pad is at a crucial thickness. Some cars are equipped with a electronic sensor that illuminates on the dash when the pad is at a low measurement. Other noises can develop from aged parts due to their wear pattern introducing dust between the friction materials or excessive overheating of the braking system due to down hill braking or a lot of stop and go driving, replacement would be advised to eliminate noise but this is not an unsafe condition.
3. Engine Oil:
   • Engine oil lubricates internal engine components to avoid friction of moving metal parts. Components consist of oil, oil filter and oil pump. The spinning motion of the engine activates the oil pump which cycles oil all throughout the engine through tiny passage ways to lubricate crucial engine components in order to prevent damage and wear. Oil is returned into the oil pan after passing through the oil filter and picked up by the oil sump and is fed into the oil pump.
   • How often should I change my oil? Your vehicle’s manufacturer has designated the correct interval for all services which should be followed for optimum vehicle performance and longevity. Typically modern cars all use full synthetic oil which can last over 5k miles. However most mechanics usually do not recommend to exceed this interval as most manufacturers have increased this interval without changing any aspects of the engines internal design and only do it to lower the cost of ownership throughout the car’s life.
   • DIY oil change tips and steps. If you are mechanically inclined the oil change is a simple process. The important part is to make sure that when you are done you have enough oil in the engine and that it does not leek. After completion of an oil change look underneath your car to make sure that the drain plug is secured and is not leaking, as this is the time to prevent future issues. The proper way to check the oil level and receive the most accurate measurement is after the car has sat for a couple of hours as this way all the oil has settled in the pan. The best time to do this is before starting your car in the morning.
   • Choosing the right oil for my car. The main difference between oils is simply how refined it is. Many years ago all cars expected conventional oil, Service interval used to be every 3k miles. Most cars today do not accept this oil and require a synthetic blend. Blend oil is a great way to increase the strength of your oil without increasing the cost too much. Synthetic blends is the most common oil used today, it is designed for service intervals of 5k miles. Full synthetic oil is the most premium and most refined oil available. Full synthetic should not be mixed with other oils as it breakdown when mixed and does not offer all of its benefits. Oil has additives which allow it to function; anti-wear, anti-foam, anti-sludge, detergent, dispersant, viscosity improver. Different brands have different performance aspects but in all cases synthetic oil holds a higher film strength than non synthetic oil. It is not recommended to mix synthetic oil with non synthetic oil as they can breakdown and create additional internal engine wear. Full synthetic oil is required for most new vehicle. however the interval should be closely monitored and serviced more frequently based on hard driving conditions.
4. Battery System:
   • The battery serves a crucial role in initiating the engine’s operation. The job of the battery is to start the engine. Components consist of a battery, terminals and lead wires. The starter motor uses battery power to start the engine after which the alternator charges the battery to replenish the electricity depleted during startup.
   • How to jump-start a car? The proper way to jump start a vehicle is with an external jumper pack. This is a chargeable devise that connects to and supplies power to any battery without harming it. Jump starting a vehicle from another car is not recommended due to different power outputs from different types of cars depending on their electronics set up and engine size. If you have a jumper pack available you hook up to the battery positive lead to the positive terminal and the negative lead can go on any bare metal of the frame or negative terminal as they care connected in one circuit. When having to use another vehicle’s power you must do the same regarding leads contact however a smaller engine car may not create enough power with the engine off or just idling, (maximum charging output is generally around 2k rpm, however a large vehicle charging system may overpower a smaller vehicle’s by design and therefore the engine should be off. Jump starting your car from another car is more of an artform nd not recommended by car manufacturers today.
   • Signs of a dying car battery. Batteries tend to fail at a 5 year mark, as well as with significant weather changes such as going into winter or even going into spring. The best way to know your battery’s health is by having it inspected regularly with your maintenance service intervals. It is possible that when testing a borderline failing battery it will make it worse as it is on its last leg and may give off additional symptoms after being tested. One way to judge the battery health on your own is just to pay attention to the engine spin when when starting your car, you may notice its a slower and quieter spin.
   • Replacing a car battery: step-by-step guide. If you are not comfortable performing this service please reach out to a professional in order not to case any damage to your electrical system. When replacing the car’s battery it is a good Idea to make sure that the new battery has the same dimensions, power output, and post polarity. You may also use an energy saving device so that your electronics do not reset such as at he clock and radio presets and settings.
5. Tire System:
   • Tires are filled with air to maintain proper contact to the ground. Many people do not realize the role that the tires have in your car’s suspension, they are your contact to the ground and have the ability to make your ride soft or hard. The less air you have the wider the footprint allowing better traction to some degree, and the more air in the tire the less of a footprint the tire has allowing the car to be more efficient. Keep in mind there are enormous drawbacks from too much air such as explosion due to over inflation as well as tires coming off the wheel due to underinflation. Please consult a professional prior to adjusting your tire pressure. the best rule of thumb is to follow your manufacturer’s tire pressure setting located on the driver’s door jamb of your vehicle.
   • Understanding tire pressure and maintenance. Most car’s are running 35psi, some low profile tires may need more, but that is a general spec. if you drop from 35psi to 30psi it may be a natural loss of air. Remember a law of physics, pressure fluctuates with temperature. Tire pressure will also be affected, it is about 1 psi for every 10 degrees. if your tire air pressure drops below 20 you car will not maneuver as designed and can become dangerous, this needs to serviced as soon as possible. if your tire cannot hold at least 10 psi driving in that condition may case damage to your wheel as the tire may break the bead and become dislodged.
   • Tire rotation: why and how often? Tires should be rotated every oil change as they are typically every 5k miles and give the technician a opportunity to inspect the under car safety points like brakes, steering and suspension. Tire manufacturers state that tires need to be rotated every 6k miles in order to achieve maximum tire life. Cars that have staggered tires meaning rear tires are larger than front tires (performance set up) will only achieve 50% of the expected tread life since they cannot be rotated. Today’s street tires are mostly radial design and get rotated from front to back only for a number of reasons. Although some manufacturers do have recommendations for cross rotations, most mechanics will not perform this unless requested due to the wear patterns that are created from rough roads, causing tire to becomes noise when spun in the opposite direction.
   • How to change a flat tire? Most cars are equipped with a spare tire and tool kit. When the tire is flat and adding air is not an option you may install your spare tire using the provided tool kit. Keep in mind some car have a wheel lock key, make sure you know where it is at all times so that you can locate it in the event you need to replace your tire. A Spare tire can be a full size or it may be a space saver (donut) this non full size tire is not safe to drive at freeway speeds and has a speed limit of 50 mph and should not be driven on for a more that 50 miles in total. Some modern cars no longer come equipped with a spare tire as manufacturers are trying to reduce the weight in order to achieve higher fuel efficiency. You may find an air inflation device and that is all, if you puncture is causing a very slow leak, you can air up to the recommended pressure and get to a service location. Similar to a product called fix-a-flat, which once used leaves a coat inside the tire attempting to seal punctures but also making the tire unrepairable.
6. Cooling System:
   • Cooling system components and operation: The cooling system ,maintains the vehicle operating temperature. Components consist of radiator, water pump, thermostat coolant hoses an the engine block. The water pump is spun by the engines power to move coolant through the engine block’s cooling jackets which are located at the areas that generate excessive heat from the engine to lower the engine’s temperature. The thermostat is open when engine reaches operating temperature and coolant or water flows into the radiator. Passing through the tiny lines which have air blowing around them either by the vehicle traveling at a high rate of speed or by switching on a fan to simulate air moving through the cooling fins of the radiator. Thermostat remains closed when vehicle is not warmed up in order to allow the car to reach proper operating temperature.
   • Signs of a failing radiator. Over time due to corrosion and lack of maintenance radiator may become plugged and not allow enough coolant to pass through it at which point it would need to be replaced. A failing radiator is the last thing that can be determined from performance alone as the system utilize several mechanisms to cool the engine.
   • How to flush the coolant system? Most modern vehicles have a cooling system service interval at 100k miles. At this service interval all coolant is drained and new coolant is added. After which a air bleed process must be carried out in order to eliminate any air bubbles that have developed during the emptying state. In some cases especially with older cars thermostat replacement would be recommended to maintain proper operating temperature.
   • Overheating causes and solutions. If one or more of the cooling system components malfunctions the cooling system will not function properly and may result in overheating of your engine. Essentially if the cooled water cannot make it through the engine’s cavities you vehicle will not maintain operating temperature. To aid your engine’s ability to cool down there are two options you have to use in an emergency situation: you can turn on your car’s heater to allow some of the engine heat to escape, or you may turn on the a/c which will initiate a condenser fan located near the radiator to allow more air to pass through the radiator. If you are out of coolant nothing will work and immediate tow would be recommended. An engine can only run for maximum 5 minutes before it reaches and exceeds the operating temperature. If engine exceeds operating temperature it will overheat internal engine components such as the cylinder head which is where heat is generated the most. The cylinder head has a mating surface that has a precise tolerance and attaches to then engine block. The head gasket is the first thing to go when overheating condition becomes excessive, in some case the cylinder head itself may crack and require replacement followed by other internal engine components that if damaged would constitute an entire engine rebuild or replacement. Have your system routinely inspected to ensure proper function to avoid this.
7. Transmission Troubles:
   • Transmission components and operation: Transmission’s job is to provide usable power. Components consist of gear selector, gear indicator, speed sensor, computer, clutch, and torque converter for automatic transmissions. Engine creates power and provides a spinning motion and the transmission has different gear ratios to change the amount of toque to be applied to the wheels which is calculated to move vehicles of different weight. When taking of from a stop the the car needs to be in a low gear which is the slowest spinning but results in most torque allowing the vehicle to gain speed. Shifting gears is the process by which the transmission allows the vehicle to increase speed without increasing the revolutions of the engine. The highest gear ratio will allow maximum speed to be achieved but will subsequently not create enough torque at low speed to move the vehicle. The gear selector allows the driver to choose between R which will move the vehicle in reverse at a similar rate as first gear as it offers the amount of torqued needed to move at low speeds. D will allow the vehicle to travel forward and change gears automatically to allow acceleration to maximum speed. the lower options such as 4 would allow the vehicle to accelerate but not shift above 4th gear, same it true for 3, 2 and 1 or L. L means low gear which is needed for maximum torque therefore when a challenging hill climb is needed the lowest gear possible should be used because a high gear will not provide sufficient torque and will overwork the engine causing it to overheat or wear excessively. In a manual transmission you are involved in the gear changing process however in a automatic transmission it used pressure to sense the need for changing gears and do so automatically to maintain usable power. CVT transmissions are constant variable transmissions use dual clutches to push and squeezy a band that slowly changes gear ratios without the use of sprocket gears. The Engine output shaft spins and engages the transmission input and the chosen gear will apply torque to the transmission output shaft which spins the final drive components that send power to the wheels to make the car go.
   • Symptoms of a failing transmission. When the transmission service is not performed or low fluid level condition develops this will cause the transmission to either slip or not change gears at all causing your car to not have usable power, meaning the engine is revving but the car is not going. In some cases this can be addressed by simply adjusting the transmission fluid level and in others a transmission rebuild or replacement would be needed.
   • How to check and change transmission fluid? All cars have very specific and different processes to check the transmission fluid. Most cars that have a dip stick must be checked with the engine running and fluid level should be between the marking on the dip stick. Some cars do not have a dip stick for the transmission and must be level at the fill plug located on the side of the transmission. It is best to consult a professional in order to determine the state of your transmission and fluid.
   • Transmission slipping: what to do? A transmission fluid service is a valid attempt to rectify this condition however there is a possibility that a rebuild is required. Changing the fluid on an aged automatic transmission especially one that shows symptoms may become worse after the service is performed due to the fact that transmission functions is activated by pressure and the new fluid has a detergent addictive that will clean up build up which may cause a pressure loss within the system.
8. Electrical System:
   • Electrical system components and operation: The electrical system supplies power all throughout the vehicle to achieve various tasks. Components consist of a battery, groups of wires, fuses, switches, sensors, computers, actuators, pumps, motors, amplifiers, spark plugs, and light bulbs. Electricity can be defined a electronic motive force which builds amperage when the current travels through eh circuit based on the resistance which is measure in ohms. Most systems are 12 volts which is supplied by eh battery through a fuse which protects any given circuit from acceding its designed amperage rating. A switch will allow the flow of electricity which can be activated by the driver, computer, or a sensor. Every components with require different amount of amperage and the circu9it would be design to have the proper gauged wire to withstand the heat as well as a fuse designed to fail if the amperage is exceeded. Amperage is increased when resistance is decreased. Ohms law; one volt pushes one amp through one ohm. When a particular load fails excessive current is passed through due to the decreased resistance also know as a short circuit which can also happen when wires make contact outside of the designated path. When a circuit is completed current travels from one battery post into the other, if any of the mentioned components malfunction the circuit will not be completed and system failure will occur.
   • How to replace a car fuse? You would need to locate the fuse block for the specified circuit and inspect to see if it has a break. Replacing a fuse may resolve the issue if the source of the problem has been rectified. If the malfunction is still present such as a short circuit the fuse will break again once the circuit is activated. All electrical circuits are protected by a fuse. As electricity passes through an object it creates heat. Electrical devices are designed to turn that heat into a function due to the resistance that it provides. When a short circuit develops excessive current passes through the circuit and when the amperage exceeds the design of the circuit the in line fuse will break which will stop electricity from continuing to pass eliminating excessive heat potentially causing a fire.
   • Troubleshooting car electrical issues. Most electrical issues are either very simple or extremely complex due to the limited understanding most people have of electricity and electrical systems. Electricity can not be seen, only its presence can be verified using a multi meter and other electrical diagnostic equipment. Most technicians get very creative in determining the functionality of the system due to their understanding of its functions.
   • Common electrical problems and solutions. Modern cars have more electrical systems than ever. A lot of these systems heavily rely on the car’s battery as they are functioning before the engine is started. If a car tends to sit for days at a time, different fault messages may appear during start up. Most of these concerns can be resolved with a new battery.
9. Suspension System:
   • Suspension components and operation: Your ride control is very effective way to make you car drive smooth and create a sense of comfort. Components consist of shocks, struts and springs. The spring allows the car to move up and down to remove rigidity and setting the ride height. The shock absorbers are designed to slow down the spring rate of the spring, if it were not for shocks the car would just bounce around. Shock absorbers slow down the rate of the spring and keep it from bouncing to achieve a one smooth up and down motion from every bump. When you are driving at higher rates of speed such as on the free way, your tire wants to hop up and down but the shock is what dampens that force allowing balance and stability of the ride. Struts function the same way as shocks except the are mounted to the spring in a different way that is all.
   • Diagnosing and fixing suspension problems. When inspected routinely with your regular maintenance you can ensure proper function of your suspension and increased tire life and decreased road noise
   • When to replace shocks and struts. A symptom of poor shock functionality it cupping of the tires as the shocks and strut wear they allow excessive up and down motion or hoping at high speeds causing a wave pattern to develop on you tires making them noisy, can be felt by running your hand across over the tread. Another indication is excessive leaks, as car manufacturers allow some seepage of the shock and struts and consider it to be normal.
10. Steering System :
    • Power steering system components and operation: The steering wheel turns the wheels to point the car into the direction of travel. Components consist of steering wheel, steering intermediate shaft, steering gear box (or rack and pinion), power steering pump, steering linkage and steering knuckle. The steering linkage will vary based on different brands design and in some newer cars the pump is replaced with eclectic power. When you spin your steering wheel the steering shaft going out of the cabin is spinning a gearbox which is also know as a rack and pinion. The gearbox uses hydraulic power created by the power steering pump which is a externally mounted on the engine and uses engine’s power to build pressure into the hydraulic lines to engage power steering. The steering linkage which has the adjustment points for alignment setting will push the steering knuckle to which the wheel is directly attached. The steering knuckle allows the wheels to pivot in either direction to move the vehicle into the selected direction of travel
    • Steering wheel vibration causes. Commonly unbalanced tires may cause a vibration that can be felt at higher speeds. When tires are excessively worn they may provided the same result. Your steering system employs mechanisms that translate your steering wheel position into your wheel positions angles allowing your car to make turns. The steering mechanism has joints that swivel and may create free play overtime. if there is any failing component that needs to be addressed immediately in order to avoid disconnection and loos of steering ability.
11. Air Conditioning Explained:
    • Air conditioning system components and operation: Air conditioning system is a refrigerant system that provide cold air to lower the temperature in the cabin of the vehicle. Components consist of an a/c compressor, a/c lines, receiver drier, expansion valve, condenser, evaporator, blower motor and the climate control unit. The a/c compressor is externally mounted to the engine. It is powered by a belt which uses the engines power and has a clutch which engages when commanded by the climate control unit to pressurize a gas called Freon through a/c lines. The Freon travels through the expansion valve and into the evaporator to create a low temperature zone from which the blower fan pushes air through to bring cold air into the air vents of the cabin. The Freon than travels to the condenser to be cooled and than into the receiver drier prior to being retuned into the a/c compressor.
    • Why is my car AC not working? Most common cause is a loss of Freon. Freon can leak from various areas it may also evaporate over time.
    • DIY AC recharge and troubleshooting. When inspecting any issues with the A/C system a machine must be used to test system pressure and introduce Freon in to the system to a specified amount. If a leak is very slow an cannot be found with the machine a UV dye is introduced into the system along with Freon recharge to the specified amount. A second inspection is needed with an ultra violet light if the system begins to fail in a short amount of time. DIY is not likely as the gas is not available to the public. The A/C refresh kit that is available is not actual Freon it is only an addictive that can help to boost the system pressure, but only helps if you’re slightly low on Freon. In most cases there is a leak than must be addressed before Freon can be added.
12. Fuel System Explained:
    • Fuel system components and operation. The fuel system provides fuel which is a chemicals charge for detonation, ignited by the spark plug to create combustion for an internal combustion engine. Components consist of a fuel tank, fuel pump, fuel lines, fuel filter, fuel rail, fuel injectors air fuel ratio sensor oxygen sensor and a computer control module. The fuel pump builds fuel pressure from the fuel tank to the fuel injectors between 35 and 50 psi. The fuel travels through the fuel lines directly out of the fuel pump which draws fuel from the tank sometimes passing through an external fuel filter up to the fuel rail to which the fuel injectors are mounted. Fuel injectors spray and atomize fuel when commanded by the computer based on various inputs. Fuel injection system can be closed loop or open loop. A closed loop system is when an oxygen sensor reports the amount of burned fuel in the exhaust chamber to adjust a richer or leaner air fuel ratio. The computer has a fuel map which allows the output of fuel via the injector based on engine rpm and throttle percentage as well as some additional inputs from engine temperature, speed of travel and air fuel ratio readings. Fuel is supplied into the engine at the exact moment it is needed as the engine is in the compression stroke, just before the spark plug ignites the air and fuel mixture.
    • Fuel octane rating: Higher octane fuel is more combustible and is used in high compression engines. Fuel itself is a cleaning agent as well as a cooling agent in addition to being a chemical charge for combustion. When octane is too low for your engine pre detonation may occur as the fuel is compressed to its maximum point and is sooner than the compression stroke is competed therefore creating detonation before the spark plug ignites the fuel. An engine knock or a pinging sound is heard when the two flame fronts meet once the spark plugs ignites the mixture. Most modern cars are equipped with a knock sensor which delays the ignition timing to eliminate this condition it also lowers the fuel efficiency as well as crating additional carbon build up. Always follow the octane rating as recommended by the manufacturer for best fuel economy and overall health and performance of your engine.
    • Symptoms of a clogged fuel injector or failing fuel pump are: No start, poor acceleration, engine misfire, erratic idle.
    • How to clean a fuel system? Carbon build up is a byproduct of burning fuel as it builds up in different areas it restricts the flow of fuel and air into the engine. Fuel injection kits are a good way to remove some of the build up but using good gas is the best way to reduce carbon build up. The only difference between fuel brands is the additives they add to their fuel and these additives are designed to help clean the engine internals of carbon build up.
13. General Maintenance:
    • How to change spark plugs? Spark plugs are located in the cylinder head and are connected through either an ignition coil or ignition wires which run from a distributor. To replace the spark plugs you must disconnect the ignition coil or wire to access the spark plug and remove it with a spark plug socket. It is best practice to inspec the spark plusg to identify the quality of the combustion in the engine by looking for signs of fouling due to carbon or oil or overheating by finding the arcing points. A new sparkplug must be gaped accordingly than reinstalled into the cylinder head and ignition coil or wire must be reconnected.
    • When to replace the timing belt? Timing belt replacement is due between 8 and 9 years of the vehicles age or at 90,000 mile intervals.
    • DIY car maintenance checklist.

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