What are the symptoms of a faulty natural gas vehicle pressure reducing valve?
2 Answers
When the natural gas pressure reducer fails, symptoms such as unstable idling, difficulty in switching gas, increased fuel consumption, deteriorated power performance, and stalling while driving may occur. The pressure reducer is installed near the engine intake pipe in a location with minimal vibration, but it cannot be directly mounted on the engine. Its installation position should also not be higher than the top of the engine radiator; otherwise, the heating water may not flow through the pressure reducer, causing it to freeze and crack. The pressure reducer assembly is equipped with an idle valve to supply gas to the engine during idling. During the decompression process of the compressor, expansion work is required to absorb heat, so the pressure reducing valve also includes a heating device that utilizes the engine's circulating water.
If your car runs on natural gas, the symptoms of a faulty pressure regulator are quite obvious. I remember my CNG vehicle had this issue before - it would struggle to start, taking forever to crank, and even when it did, the engine would shake violently like it was gasping for air. During normal driving, you'd notice significantly reduced power, sluggish acceleration especially uphill, and a sharp increase in gas consumption, meaning each fill-up wouldn't get you far. The scariest part was smelling that distinctive natural gas odor, like rotten eggs, which indicates potential gas leakage - how dangerous! You should immediately check the engine compartment; if you see frost on the pipes or hear a hissing sound, it's almost certainly a failed regulator. Never ignore this - it's best to pull over right away and call a tow truck to the repair shop, otherwise you might break down mid-drive. By the way, this problem usually occurs due to part aging or dust clogging, which regular maintenance can prevent.
