Question # 56

A car fails I/M with high NOx. EGR valve is commanded open, but MAP readings show no change. Fuel trims are balanced. What is the most likely cause?

Options:

A.

Blocked EGR passages

B.

Faulty O2 sensor

C.

Weak ignition coil

D.

Dirty injector

Viewing question 56 out of 72 questions
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