What does this mean?
Interpretation of OBD2 Code P0303 Subaru:
P0303 Subaru code means that the car’s computer detects that one of the engine components is not working properly. In this case, note # 3.
Possible indicators of OBD code P0303 Subaru
the engine may be difficult to start the engine may crash / break down, and / or suspect other symptoms may be present
What may cause the OBD P0303 Subaru code
Code P0303 Subaru could mean that one or more of the following happened: Wrong plug or wire Input (package) Wrong air sensors Incorrect computers
If there are no signs, the easiest thing to do is to reset the code and see if it comes back. If there are signs such as that the engine is failing or slowing down, look for all connectors and connectors that lead to the plugs (eg plugs). Depending on the length of time you spend on car accessories, it may be best to adjust them as part of your maintenance plan. I recommend plugs, plug wires, split cups, and rounds (if possible). Otherwise, look for coils (aka coil packs). In some cases, the support switch has gone wrong. If you are smelling hot eggs, your cat converter should be changed. I have also heard from time to time that the problem was with the wrong fuel.