You may be surprÂ­ised to discover that a carbon monoxide (CO) detector really isn't a complicated piece of equipment. Housed inside a plastic chamber approximately 3 inches (7.6 centimeters) in diameter are parts that work in unison to alert a househoÂ­ld when lethal gas is detected.
This type of noise is usually caused by malfunctioning valve lifters or an exhaust manifold leak. If the noise lasts for more than a minute and completely disappears or dimishes after the engine is warm, the most likely cause is an exhaust manifold leak.
Home Â» Car Maintenance Â» What Causes Engine Pinging. What Causes Engine Pinging Posted on Autos.com Editor. in Car Maintenance. on October 7, 2013. Engine pinging or knocking occurs when a pocket of the air and fuel mixture detonates ahead of the flame front ignited by the spark plug. This premature ignition causes a drastic increase in the pressures present in the cylinder, and when the two flame fronts meet, the characteristic engine pinging noise is heard.