If the engine won’t crank, you first need to verify if it’s turning over. If the engine won’t even spin, then verify that the battery cables are tight and clean. If they are not clean, use baking soda and a wire brush to clean the posts off. If the cables are good, confirm that the battery is holding a charge. You can have this checked at an auto store unless you have a load tester. Volt meters can mislead you by showing a 12+ volt reading, until the key is turned. Replace the battery if it will not hold a charge. If the battery holds a charge but still dies after starting and stopping a few times, then the alternator could be at fault. A quick test for most alternators is to take a screwdriver and carefully touch the back center of the alternator. If you touch this shaft when the car is running, it will be magnetic and the screwdriver should stick to it very well.
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The idle air control is a control system used on fuel injected cars. The idle air control or IAC valve controls the idle speed of the engine. The IAC valve is controlled by the ECM (computer). The computer gets it’s information from the rpm which is supplied by the distributor, crank or cam sensor. The IAC valve moves in and out to bleed air behind the throttle plate. This air bleeding is the same as opening the throttle plate. The idle speed can be controlled precisely the throttle plate which isn’t controlled as well. Air conditioning will drop the idle speed down and will kill the engine if the IAC doesn’t work well. The idle air control will be located on the side of the throttle body. The IAC can become sticky after time and will cause the the engine to surge, rev or stall the engine. The valve can be removed and cleaned if not too severely worn. Usually the valve needs to be replaced. Make sure the gasket looks alright. Also make sure the idle air control is secured well and doesn’t leak air, or the engine will rev up.
A standard car’s distributor ignition coil can be tested by checking the ohms reading. Ohms can be read on a volt/ohms meter. Ohms is a unit of measure for the resistance that a wire or coil has. Ignition coils should be measured on the primary coil between batt and tach terminals. The batt is the coil ground. To check the secondary coil, check the ohms between the batt terminal and where the coil output wire plugs into. If the ohms read zero the coil connection is broken and the coil is no good. An open coil reading zero is the usual culprit of coils. Don’t test through the output wire though. The primary coil should read between .7 ohms and 1.7 ohms, if outside this range replace it. The secondary coil should generally read between 7.5K ohms and 10.5K ohms. If the ohms are not within the specified range for that paticular car, replace the coil. Coil resistance will also change and vary if the coil is hot or cold. This a generalized ohms range that fits most distributor coils. Another thing to remember is that sometimes a coil will only read bad after it gets hot. It may work intermittently after it gets hot also. Coil packs will generally read around .3 to 1.5 ohms on the primary side and 12.5K to 13.5K ohms on the secondary side. These figures will get you reasonably close to where the coil’s ohms need to be to work properly.
Intercoolers have been used on turbocharged and supercharged engines for quite some time now. When used on a supercharged engine they are often called aftercoolers. Turbos are the most common usage for intercoolers though. Any engine that uses an air compressing device such as superchargers and turbos can benefit from intercoolers. When the air gets compressed it can heat up dramatically, up to 300 degrees F. This dramatically reduces the compressed air density and limits the maximum boost. The high intake temperatures can increase the chance of detonation in the engine, causing major engine damage. An intercooler can fix this problem.
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Engines are simply an air pump. The more air you can get in and the more exhaust you can move out, the more power you can make. Superchargers are one way of packing more air into an engine. Superchargers or blowers as they are sometimes called have been around for a long time and are still currently being used on some production vehicles. There have been many different types of superchargers made but I will focus on the two most popular versions. One being called positive displacement or roots type and are generally referred to as blowers. These are the style most used on muscle cars due to the ease of setup on a v-8 with a carburetor. They are also widely used on drag cars for street and professional racing. Some of these cars make insane horsepower in the thousands. The blower has an advantage, because it compresses air even at very low speed it also creates alot of torque. This gives the engine very good response and power from idle up. That is why drag racers like them so much, they are very predictable from launch and have almost no lag time.
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Auto air conditioning can easily be changed from old R-12 to new R-134 refrigerant. The new style R-134 refrigerant can be used in R-12 systems as long as the oil is included with the installation of the new refrigerant. No new seals or any other components should need to be replaced. Your car’s system should be completely empty of the old R-12, which is supposed to be contained and removed by a certified refrigerant technician. When doing anything with ac you should first understand that there are two sides of the system. The high pressure side will be the side with the smaller diameter lines, this side is very high pressure and should be avoided. The low pressure side will have the larger diameter lines and will have the condenser. The condenser looks like an aluminum canister of about 4″ in diameter and appx. 6″ long. The fill port will probably have a plastic cap on it. The port is a valve that looks like a air fill on your car tires. You will need a kit composed of an adapter and the hose used to fill the system with. Some types of cars need different adapters.
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Nitrous is a cheap way to make a lot of power. Nitrous comes in kits and can increase your power anywhere from 50 hp to 400 hp. The nitrous is limited by the engine’s ability to handle the power. A 200 horsepower engine is not meant to handle 400 hp of nitrous. An engine built correctly can handle massive amounts of nitrous. On a standard engine the ignition will need to be retarded. The fuel will also have to be increased either by the fuel map or a fuel nozzle. Nitrous was first used in aircraft to help the plane gain alot of altitude very quickly. Soon after people realized the potential and set up systems on cars. Unfortunately at this time there were not many good ways to control fueling verses nos being sprayed. Many people blew up there engines because of having a lack of understanding of nitrous. Today kits have come a long ways and have the setup down to a science. Nitrous can be very reliable as long as it’s not used excessively per engine setup.
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