Vehicle
Mazda RX-7
The rotary coupé, and almost nothing about ordinary engine diagnosis applies to it. A Wankel has no valves, no camshaft and no conventional compression test — its health is read as three individual chamber pressures with a rotary-specific gauge, and a low reading means apex seal wear rather than anything a piston engine would suggest. The FD's sequential twin turbochargers are controlled by a set of vacuum-actuated valves and hoses often described as the rat's nest, and a single perished hose there produces boost faults that read as a failed turbocharger; it is the first thing to check and the last thing most people check. Oil injection into the chambers is by design, so oil consumption is normal and a low level is a real risk to the seals.
Generations
-
SA22C and FB 1978–1985
The first-generation rotary, naturally aspirated and largely carburetted — apex seal wear is read as three chamber pressures, not as compression.
- Body styles
- Coupé
- Platform
- Mazda SA
- Engines
-
- 1.1 rotary — 12A · petrol
- 1.3 rotary — 13B-RESI · petrol · 13B
- 1.1 turbo — petrol
- Transmissions
- 4-speed manual · 5-speed manual · 3-speed automatic · 4-speed automatic
- Drivetrain
- Rear-wheel drive
-
FC3S 1985–1992
13B rotary, naturally aspirated or single-turbo; pre-dates OBD-II and needs Mazda's own diagnostic connector.
- Body styles
- Coupé · Convertible
- Platform
- Mazda FC
- Engines
-
- 1.3 rotary — petrol · 13B naturally aspirated
- 1.3 turbo rotary — 13B-T · petrol
- Transmissions
- 5-speed manual · 4-speed automatic
- Drivetrain
- Rear-wheel drive
-
FD3S 1992–2002
13B-REW with sequential twin turbochargers; a single perished vacuum hose in their control circuit mimics a failed turbo.
- Body styles
- Coupé
- Platform
- Mazda FD
- Engines
-
- 1.3 twin-turbo rotary — 13B-REW · petrol
- Transmissions
- 5-speed manual · 4-speed automatic
- Drivetrain
- Rear-wheel drive
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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