Question # 7

A vehicle has elevated CO and HC levels. Scope shows normal spark, compression is balanced, but fuel trims are negative. What is the likely root cause?

Options:

A.

Stuck-open injector flooding fuel

B.

Faulty catalytic converter

C.

Leaking vacuum hose

D.

Faulty O2 sensor

Viewing question 7 out of 72 questions
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