I am having trouble with my diesel truck which has 195,000 miles on it. I've had to change out the exhaust filter at least two times recently and it is filling up again.
Hello, the engine computer is supposed to put the system through a regeneration process to burn off the soot and ash that builds up inside the filter. This truck is equipped with a DEF (diesel exhaust fluid) system, which sprays a urea solution into the exhaust to help burn off the ash and soot in the exhaust. The DEF system might not be injecting enough fluid for it to perform a regeneration cycle and burn off the soot. The vehicle should be checked for codes. Even though there is no Check Engine Light, there might be codes indicating a fault. If you would like help with this, a certified technician from YourMechanic can come to your home or office to have this issue inspected.
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