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.
It sounds as if one of the lifters is not pumping up. I don't think there is any way to confirm other than sound, and misfire codes without pulling the head. I had a lifter go bad on my SS shortly after a b1 cam was installed, and it sounded exactly as you are describing.I went with the regular Comp-Cams lifters (not the R's, R's are noisy). don't think there is any way to confirm other than sound, and misfire codes without pulling the head. I had a lifter go bad on my SS shortly after a b1 cam was installed, and it sounded exactly as you are describing.