[1] Turgeon continued to assist Bishop Plessis in the administration of the diocese, while also fulfilling a number of different duties at the seminary.

The strain of managing both academic and diocesan responsibilities undermined his health, and in 1819, as a respite, he accompanied Plessis to Europe.

In February 1834, Pope Gregory XVI appointed Turgeon titular bishop of Sidyme and coadjutor of Archbishop Signay.

Of a mild disposition, he was often able to mediate disagreements between Archbishop Signay and Ignace Bourget, Bishop of Montreal.

In November 1849, due to ill health, Signay turned over administration of the diocese to his coadjutor.