These are a few Pictures of our "Reworked" GM Harnesses. Reworked meaning, we've made them "Stand Alone" units. They will work with as few as 3 Wires Hooked up! We DO NOT make harnesses... we leave that to GM. Our Business here at LSx4U is to make Stand Alone LS Harnesses & ECM for use in Off Road Vehicles or application that DOES NOT need to pass State or Federal Emissions test. If your transplanting an LS Engine into an older vehicle you have a shot at passing the emissions test set up for that year vehicle!
The No Trans Control Engine Harness Needs Only 3 Wires To Run... Talk About EASY!
Below Is the "Express" harness with the longer main trunk so that the ECM can be mounted inside the vehicle!
How does an O2 sensor work?
An Oxygen sensor is a chemical generator. It is constantly making a comparison between the Oxygen inside the exhaust manifold and air outside the engine. If this comparison shows little or no Oxygen in the exhaust manifold, a voltage is generated. The output of the sensor is usually between 0 and 1.1 volts. All spark combustion engines need the proper air fuel ratio to operate correctly. For gasoline this is 14.7 parts of air to one part of fuel. When the engine has more fuel than needed, all available Oxygen is consumed in the cylinder and gasses leaving through the exhaust contain almost no Oxygen. This sends out a voltage greater than 0.45 volts. If the engine is running lean, all fuel is burned, and the extra Oxygen leaves the cylinder and flows into the exhaust. In this case, the sensor voltage goes lower than 0.45 volts. Usually the output range seen is 0.2 to 0.7 volts. The sensor does not begin to generate its full output until it reaches about 600 degrees F. prior to this time the sensor is not conductive. It is as if the circuit between the sensor and computer is not complete. The mid point is about 0.45 volts. This is neither rich nor lean. A fully warm O2 sensor *will not spend any time at 0.45 volts*. In many cars, the computer sends out a bias voltage of 0.45 through the O2 sensor wire. If the sensor is not warm, or if the circuit is not complete, the computer picks up a steady 0.45 volts. Since the computer knows this is an "illegal" value, it judges the sensor to not be ready. It remains in open loop operation, and uses all sensors except the O2 to determine fuel delivery. Any time an engine is operated in open loop, it runs somewhat rich and makes more exhaust emissions. This translates into lost power, poor fuel economy and air pollution. The O2 sensor is constantly in a state of transition between high and low voltage. Manufacturers call this crossing of the 0.45 volt mark O2 cross counts. The higher the number of O2 crosses counts, the better the sensor and other parts of the computer control system are working. It is important to remember that the O2 sensor is comparing the amount of Oxygen inside and outside the engine. If the outside of the sensor should become blocked, or coated with oil, sound insulation, undercoating or antifreeze, (among other things), this comparison is not possible.