Methods and systems are provided for diagnosing a particulate filter located in an exhaust runner of an engine cylinder. In one example, a method may include flowing exhaust from a first cylinder through a first particulate filter in a first runner, and flowing exhaust from a second cylinder through a second particulate filter in a second runner. The method may further include adjusting engine operation in response to particulate filter degradation, the particulate filter degradation distinguishing between degradation of the first and second particulate filters based on an exhaust pressure pulsation timing relative to combustion events.