The exhaust recirculation valve (EGR) on the 1996-2012 Acura RL may fail, causing:
The EGR valve has open and closed positions, and opens or closes on command from the computer.
Exhaust gases constantly pass through the valve when it is open, leaving carbon deposits on the valve. These carbon deposits may lead the the valve sticking in the open or closed position.
To correct this issue, sometimes it is sufficient to clean the valve, but replacement is recommended in all cases.
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