Car Repair World

Emissions Test Failed Many states now use a simple Onboard Diagnostics (OBDII) plug-in check instead of a lengthy tailpipe emissions test to verify emissions compliance. The OBDII tests are only used on 1996 and newer vehicles, and may be used in combination with a separate tailpipe test in certain situations (the rules vary from state to state). Symptom: Failed Emission Probable Causes: Eleven monitors Catalyst Monitor Misfire Evaporative System EGR System Fuel System Heated Catalyst Secondary Air System Comprehensive Component O2 Sensor O2 Sensor Heater A/C System Refrigerant The OBDII onboard diagnostic system that is used on all 1996 and newer passenger cars and light trucks (as well as a few 1994 and 1995 models) will set a fault code and turn on the MIL lamp if it detects ANY problem that MIGHT cause emissions to exceed federal limits by 1.5 times. Notice, we said MIGHT cause emissions to exceed limits. The actual point at which a code is set is de...

Emissions Working Of Emission Control System In Car Helpful Information Emission control systems have been incorporated into automobiles to prevent pollution by limiting the amount of partially burned and evaporated gases into the atmosphere. These systems have been efficient in reducing the air pollution caused by automobiles to a large extent. Increased engine efficiency and lighter vehicle construction has also contributed to helping reduce emissions. The different aspects of emissions are tailpipe emissions, life cycle emissions and evaporative fuel emissions. Unspent fuel vapors are known as the main contributors to air pollution. These omitted gases consist of carbon monoxide, hydrocarbons, carbon dioxide and nitrogen oxide. Lifecycle emissions are byproducts which are released into the environment during the manufacturing, maintenance and disposal of the vehicle. These products include volatile solvents such as auto paint and lubricants, manufacturing plant waste...

Egr Valve Working Of EGR Valve  Helpful Information An EGR valve also helps cool combustion temperatures to stem engine detonation or pinging while the engine is under load. The operation of the valve begins while engine vacuum is lowered due to throttle position and declines as maximum vacuum returns (idle.) Carbon can build up along the valve passages so occasional maintenance is recommended. Step by step instructions on how an automotive EGR valve works. This article pertains to all exhaust gas recirculation equipped engines. Step 1  - An EGR ( exhaust gas re-circulation ) valve is designed to lower NOX (NO2) gases that occur in the combustion chamber when temperatures reach over 3,500 degrees Fahrenheit. NOX gases have been proven to cause brain damage in humans, therefore EGR valves have been mandatory on most vehicles since 1976. An EGR valve controls exhaust gases and allows them to enter the intake manifold and flow into the combustion chamber at certai...