Check Engine Light on Due to Clogged EGR Passage in Intake Manifold: Mercury Cougar Muffler & Exhaust

Problem overview

The Check Engine Light can illuminate with codes due to the lack of EGR (exhaust gas recirculation) flow caused by the intake manifold passage plugging up with carbon and oil. The EGR valve has to be removed and the passage cleaned thoroughly. Partial restriction of this passage can cause Smog test failures for the NOx emissions without causing a drivability symptom.

19 people reported this problem

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Mercury Cougar vehicles with this problem

5 model years affected

Average mileage: 159,472 miles

(122,338 - 194,000)

Repairs related to this problem

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Check Engine Light on Due to Clogged EGR Passage in Intake Manifold on Mercury Cougar

Problem overview

Mercury Cougar vehicles with this problem

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