Cadillac DeVille Problem Report

Cadillac DeVille Check Engine Light Due to Gas Cap or Catalytic Converter

(2 reports)

Two likely causes for the Check Engine Light to illuminate would be a loose or worn gas cap or a faulty catalytic converter.

I keep getting MIl Code P0440, and have repaired everything in evap system w/o curing this problem. -
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Illumination of the Check Engine Light can be caused by a loose or worn gas cap.
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