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Question # 53

A vehicle fails I/M for high NOx. The EGR valve is commanded open, and passages are clear, but NOx remains elevated. Catalyst efficiency test also fails. What is the next corrective action?

Options:

A.

Replace catalytic converter

B.

Replace oxygen sensor

C.

Replace PCM

D.

Replace throttle position sensor

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L1 Overview

Name Automotive Service Excellence Level 1
Code L1
Vendor Skilled Trades
Certification ASE

L1 Questions