1998 Mercury Sable LS After Fuel Pump Replacement: P0401 Code Explained
After replacing the fuel pump in my 1998 Mercury Sable LS a few weeks ago, I noticed the 'Check Engine' light came on the next day. The diagnostic tool showed code P0401 — indicating a diesel particulate filter or exhaust system issue. Is this a coincidence after fuel pump replacement? Could there be a connection between the two repairs? I'm looking for clarification on whether the fuel pump change could have triggered or contributed to the P0401 fault, and what steps I should take next to diagnose and fix it.