There are a lot of "high performance chips" on E-bay, But Which one is right for your car, And Won't Cause malfunctions or serious ECU (Engine Control Unit) damage? Well, the answer to this question, however, is not so simple. You must look into the function of these units. For example, many "computer chips" are not really chips at all, but a tiny resistor you splice into a wire on your vehicle's IAT (Intake Air Temperature) sensor, or into the Coolant Temperature Sensor. On many newer, more computer-reliant automobiles, these "chips" will cause various malfunctions, such as the MIL (Malfunction Indicator Light) or "CHECK ENGINE" light turning on in your vehicle's instrument panel. Other than a nuisance, it is a very important function of your vehicle's computer system. Without it, you could have a serious problem, that you would otherwise not know about, that could be causing serious damage to your drivetrain. Or it could just be a small, but important thing, like losing fuel mileage, due to a malfunction in your vehicle's ignition and/or fuel system.

           Many people wonder, "how do these ECU's And 'Performance Computer Chips' work"? Well, your vehicle's ECU works by receiving information from various sensors in the engine, exhaust system, and transmission. it interprets these signals and tells the fuel and ignition system how to adjust in order for the engine to run efficiently and properly. The "resistor type" chips work  by altering the signal and reducing the voltage sent to the ECU by the IAT, or coolant temperature sensors. This tells the ECU that the air coming into the engine is cooler than it actually is. the computer adjusts the fuel curves. (how long the injector stays open, and when to open)  This means more fuel is pumped into the cylinder, but this does not always mean more power. When you put more fuel into the cylinder, without more air, you will actually lose power. This is because the ECU is getting a false-reading of the temperature and density of the air. This, in-turn, makes the oxygen sensors tell the ECU there is too much fuel. This causes the computer to constantly trying to adjust to the signals, and sees that one or more of them is wrong. It then turns on the MIL or "CHECK ENGINE" light, to tell you, the driver, that there is a problem. So actually, it turns into a waste of time and in some cases may cause you to make expensive repairs.

              Real Performance Computers, like JET, HYPERTECH, SUPERCHIPS, and factory-brand performance computers, will do what they claim and give your engine more horsepower and torque. These computers work just like your factory ECU, but they are pre-programmed to advance your vehicle's timing, raise the engines over-rev limiter, fuel injector opening and closing timing, and raise or eliminate your vehicles top-speed limiter. These computers work efficiently and properly by maintaining the proper air/fuel ratio, and advancing the spark timing. advancing the spark timing makes more power by making the spark fire at or before TDC (Top Dead Center), causing the combustion to start sooner, therefore the fuel is more completely burned before the exhaust valve opens.

             The fuel injector timing is also a great factor in combustion. This increase in the length of time that the fuel injector stays open causes more fuel to be sprayed into the cylinder, and with the advanced timing, combustion takes place sooner and lets all the extra fuel burn more completley and efficentley. This, put together with any other performance parts, like high-flowing air filters and a free-flowing exhaust system, makes incredible amounts of power without sacrificing fuel mileage. The bad fuel mileage you hear about from high-performance parts is from the need to feel the extra power with a lead foot. So if you drive as you normally would, you sould see the same amount of fuel mileage untill you want to use the extra power.

          The best thing to do is to read your owners manual, get a repair manual (HAYNES, CHILTONS) and read it, and you will better understand the functions of your vehicle's drivetrain. Be sure to look at how any performance part functions, and if it coencides with the operation of the normal product, with a variation, it should work to your advantage. remember some more-expensive and hard to install perfomance parts, such as camshafts, heads, and headers, need to work together to provide power. With any increase of air, and an increase of fuel in a proper ratio will always result in a gain of power. I hope you found this guide to buying performance chips and how they work helpful, and that is better enables you to make a buying decision.