Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1990 Mazda RX-7 Base, StandardFACTORY OEM SERVICE PROCEDURE
Injector Delivery Volume
- With delivery pipe and injectors removed, secure injectors tightly onto delivery pipe with wire. Install hose on injector. Install Injector Checker (49 B092 953) on injector. See Fig 1 .
- Install jumper between 2 terminals of fuel pump test circuit connector. See BASIC TESTING article for test connector location. Turn ignition on. Connect injector checker to battery voltage. Note injector volume after 15 seconds.
- Replace injectors which do not meet volume specifications. See INJECTOR VOLUME SPECIFICATIONS table. Check primary and secondary injectors in the same manner.
CAUTION:
Use care when connecting injector checker to prevent sparks around fuel area.
INJECTOR VOLUME SPECIFICATION
| Application | Oz. (cc) |
|---|---|
| Non-Turbo | 3.30-3.55 (110-118) |
| Turbo | 4.00-4.25 (1.35-1.42) |
Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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