Porsche Turbo S
The M64/60S of the 993 Turbo S is the final act of the air-cooled turbo line: 331 kW from the biturbo 3.6 with larger turbochargers, sport exhaust standard for more intense sound. The basic principle remains identical to the M64/60 — no turbo lag, spontaneous turbo character with an air-cooled boxer sound foundation — but the punch arrives earlier and lasts longer. Bottom line: the 993 Turbo S is the ultimate statement of the air-cooled era, and the engine is the core of that statement. Very rare, with only 183 produced, one of the most sought-after Porsches of all time. Technically closely related to the M64/60 and equally robust, but demands diligent care at high output.
183 units — the pinnacle of air cooling
The 993 Turbo S with M64/60S is the ultimate statement of air-cooled Porsche history: 331 kW, 183 built, AWD, sport exhaust standard. There is no better air-cooled car from Zuffenhausen. Prices are astronomical and climbing, the car is status symbol and driving machine in one. Drive a Turbo S and you drive the finale of an era.
Engine Weaknesses 5
The plain bearings in both KKK turbochargers wear at high mileage. Oil flow ceasing after shutdown without a cooldown period accelerates wear. Replacing both turbos at the same time is recommended.
Symptoms: Whistling from the turbo; rising oil consumption; blue smoke especially on cold start; pressure drop at high RPM.
Plastic valve covers leak under heat and age. Metal press-fit inserts work loose. Oil drips onto the hot exhaust system — fire risk. Repair kit approx. €200–300.
Symptoms: Oil smell after driving; oil spots under the vehicle; visible oil film on the underside of the engine.
The DME relay fails through continuous energisation and heat. Typical breakdown scenario: starter cranks, engine won't fire. Often occurs after heat soaking (summer, full sun). At night or after cooling down the engine starts again — replace the relay first.
Symptoms: Engine cranks but won't start; no fuel pump priming noise after ignition ON; problem after heat soak.
The rear crankshaft lip seal becomes porous from turbo heat. Oil escapes between engine and gearbox. Repair requires gearbox disassembly.
Symptoms: Oil leak at the engine/gearbox interface; oil patch under the vehicle centre-rear.
Silicone hoses in the boost system become brittle under heat and oil vapour — on the Turbo S, stressed more heavily than on the standard Turbo due to larger turbos and higher boost pressure.
Symptoms: Sudden power loss; hissing noises under load; boost pressure fault stored.
Vehicle Weaknesses 14
Steel brake lines are particularly vulnerable to corrosion in the underbody area. Corroded brake lines are a significant safety hazard — replace completely if any deterioration is found.
Windscreen and rear window frames are prone to rust, especially if windows were replaced incorrectly. Moisture ingress and adhesive residue accelerate the attack.
Hollow sections of the rear bumper supports rust from the inside due to dirt accumulation. Regular cleaning and cavity preservation are essential.
The climate control panel can remain permanently switched on due to leakage current, draining the battery within 48 hours. Repairing the blower motor and temperature sensor is usually cheaper than a new unit.
Aluminium brake calipers corrode heavily, especially during winter use or extended storage. Pistons seize, braking becomes uneven. Rebuilding or replacement is necessary.
Steering rack tends to develop oil leaks with age. On vehicles prior to 1996 with 18-inch wheels without the factory supplement, there is a risk of steering rack fractures.
Control arm and suspension bushings age considerably. Knocking and cracking noises when compressing and steering indicate worn rubber-metal elements.
Alternator wears with age. Diodes, voltage regulator and bearing wear are typical failure causes. Rebuilt exchange units are considerably cheaper than new parts.
Hydraulic clutch cylinders leak with age. Master and slave cylinders lose brake fluid, clutch pedal sinks through to complete failure.
Central locking tends to fail due to cold solder joints in the control unit and worn actuators. Locks or unlocks immediately after the remote signal is received.
Window regulator relay clicks inconsistently. Worn cables, defective switches or damaged cable pulls are the most common causes of failures in the aged 993.
Rubber engine mounts harden with age and lose their damping function. Vibrating sensation at the gear lever and increased body vibration at idle.
Exhaust system joints corrode heavily, especially at vibration points of worn engine mounts. High heat generation and moisture in the rear section accelerate the attack.
Door hinge straps wear out, causing creaking and squeaking when opening. Heavy doors and age-related material fatigue accelerate the wear.
Reports & Tests
24 owner complaints filed with NHTSA (1993–1998). Most reported: Electrical (6), Airbags (4), Engine & Cooling (3).