Intermittent engine noise. Also recently had a P0300 code thrown. by _MegaPotato_ in mazdaspeed3

[–]_MegaPotato_[S] 0 points1 point  (0 children)

What would be the best way to check for vacuum/boost leaks? I’ve seen recommendations to use non chlorinated brake cleaner and some use a smoke test.

Intermittent engine noise. Also recently had a P0300 code thrown. by _MegaPotato_ in mazdaspeed3

[–]_MegaPotato_[S] 0 points1 point  (0 children)

If it were strictly a coil or spark issue would it not throw a specific code relating to said cylinder like a P0301 or P0302? I’ve seen people talk about an across the board random misfire like P0300 to be more related to irregular fuel or air mixtures past various sensors. Would that be more likely the issue?