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What are Diagnostics?


           What Are Diagnostics? In car repair shops, “diagnostics” generally means either determining the cause of an illuminated “Check Engine Light,” determining why your car is performing poorly, or determining why your car failed an emissions test. A vehicle may come in for all three conditions, and the cause of each may be the same. Sometimes, it is easy to diagnose the root cause of these problems; more often, it is not. Problems can be complex and may only present themselves under certain conditions. They may be intermittent, and they may be caused by multiple interacting systems. Also, the computer input devices, fuel system components, and ignition & engine control system parts that are the likely causes of your concern are expensive. Usually, when you buy one of these

Don’t throw expensive parts at your automotive problem and hope for a fix. Have your concern diagnosed correctly the first time. This will save you money.

            Some lower end repair shops, parts, and tire stores offer “free diagnostics.” Generally “free diagnostics” means that an untrained oil changer, tire buster, or parts changer will use a generic scanner and tell you what codes are stored in your vehicles on board computer. Occasionally, this work. Stored codes indicate that your vehicles computer has received a signal that is outside of the expected parameters. But the codes set can be deceptive. On many Chevy products, for example, the code P0171 indicates that the oxygen sensor on bank one of your engine is reporting a “lean” condition. Does this mean that there is a restriction in the fuel system, a problem with the fuel injectors, a problem with the ignition system, or is the oxygen sensor defective and giving an inaccurate reading? The likely answer is that the intake manifold gaskets are leaking, allowing air to bypass the Mass Air Flow sensor. Further testing is required to confirm this guess.

             Modern vehicles require highly trained and experienced technicians armed with up to date proprietary equipment and correct testing and repair information including factory technical service bulletins (TSBs) and repair manuals. This means that repair shops, like Sant Automotive, that tackle complex problems requiring diagnostics must invest heavily in terms of personnel, equipment, training, software subscriptions, and subscriptions to information sources. Let our expertise work for you. It will save you money.