Scion xD engine valve #4 failure requiring new or rebuilt engine due to sputtering and inability to accelerate on Scion xD

Some Scion xD owners report experiencing engine valve #4 failure, which leads to sputtering and acceleration issues. These issues are often accompanied by error codes such as P0300 and P0304, indicating multiple misfires with the fourth cylinder specifically affected. Additionally, a flashing check engine light may signal a catalyst damaging misfire, which poses a risk to the catalytic converter and O2 sensors, necessitating immediate engine servicing. In some cases, owners suspect that the engine may have seized due to a lack of fluid, highlighting the importance of a thorough inspection and diagnosis by professionals to assess potential damage and determine the need for a new engine. It is advisable for owners to diagnose misfiring issues promptly, address any catalyst damaging misfires, and seek professional assistance to ensure optimal performance and reliability of their Scion xD.