Porsche Turbo
The M64/60 biturbo is the crowning achievement of the air-cooled era: two small turbochargers — no charge cooling, air-to-air — give the 3.6-litre boxer a 300 kW shove, while the familiar air-cooled boxer tone remains as the base sound character, overlaid by quiet turbo whistle and a deeper, more massive exhaust note than the naturally aspirated engines. Barely any turbo lag thanks to the small twins; the engine is well usable from low revs. The 993 Turbo is a legend — it's the last air-cooled turbo 911 and thus by definition a collector's item. Technically considered very robust; the biturbo technology was mature by 1995. Weak points typically lie with the turbochargers themselves and the oil supply. It combines the character of the air-cooled heart with genuine turbo power — exactly what makes it unforgettable.
The holy grail of the air-cooled era
The 993 Turbo is the emotional peak — last air-cooled turbo 911, biturbo, AWD, six-speed manual. The sound: air-cooled flat-six with turbo foundation, zero lag, effortless power delivery. The car that "leaves nobody cold." Prices: 100k-150k and climbing — the market reflects the legend.
Engine Weaknesses 6
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.
Porsche recalled approx. 20,000 vehicles (model years 1995–1996): bio-based plastic wiring harness insulation hardens, cracks under heat and vibration — short circuit and engine failure possible. Check recall status before purchase.
Symptoms: Electrical faults, engine failure, irregular injection; in the worst case a smouldering fire in the engine bay.
The vacuum hose between the solenoid valve and wastegate ages and kinks. Boost pressure severely reduced (only 0.4 bar instead of target) despite intact turbos. Classic fault cause found after extensive diagnosis.
Symptoms: Significantly reduced power, boost pressure not reaching target, no fault code stored in the ECU.
Crankshaft lip seals are known for oil leaks, exacerbated on the Turbo by higher crankcase pressure. Repair requires engine removal and should be combined with all other seals.
Symptoms: Oil drops under the vehicle in the engine area, oil traces on the bell housing or rear subframe.
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.
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.
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).