Section 1 (Engine Controls - Tests W/Codes - 4-CYL): Summary
WARNING: This page is about a different car, the 1992 Mazda Protege, 1992 Mazda MX-3, and 1992 Mazda 323. However, it is still accessible from the selected car via links, so may be relevant.
If no hard fault codes (or only pass codes) are present, proceed to TESTS W/O CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.).