My '95 wagon had the check engine light come on.
I took the fault codes from the box near the battery, and the only code was #4 - secondary air injection.
I reset the code, nothing came back on re-start. When the light was on, there were no "driveablity" problems. Since reset, the light has not returned.
Has anyone had this occur? And secondly, what might one look for in the "secondary air injection" system as the source of the fault? Thanks for any input.

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