An exhaust gas analyzer (concentration sampling type)is being used to sample the exhaust of a vehicle that has an exhaust system leak. Which of these four gasses will read higher than normal?

Question

An exhaust gas analyzer (concentration sampling type)is being used to sample the exhaust of a vehicle that has an exhaust system leak.  Which of these four gasses will read higher than normal?

Quizplus · Accepted Answer

An exhaust system leak allows outside air, which contains oxygen (O₂), to enter the exhaust stream. This results in a higher than normal reading of O₂ in the exhaust gas analysis.

An Exhaust Gas Analyzer (Concentration Sampling Type)is Being Used to Sample