How and Why Could a Vehicle Fail an OBD Test

question 30

Essay

How and why could a vehicle fail an OBD test but pass a tailpipe emissions test?

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Definitions:

Uncertainty

A state or condition in which there is a lack of certainty or predictability about something.

Necessary Information

Necessary information refers to data or facts that are essential to complete a task, solve a problem, or make an informed decision.

Certainty

A condition where there is complete absence of doubt or the total confidence in something.

Fully Informed

Indicates a state where all necessary information has been received and understood.