Supra (A70)

1986-1993 / Coupe / Japan

All Supra (A70) problems All workshop issues

Critical Engine, 7M-GTE (Turbo)

Cooling System Inadequacy Under Boost

Symptoms

Coolant temperature climbs rapidly under sustained boost, particularly in traffic or on hot days. The temperature gauge sits higher than normal and doesn't recover quickly.

Cause

The factory radiator was adequate for 1986 driving conditions in Japan but struggles in Australian heat, particularly with any power increase. The fan clutch wears and stops driving the fan at sufficient speed. The intercooler and piping add heat to the engine bay.

Fix

Replace the radiator with an aluminium performance unit ($300-600), this is one of the highest-value modifications on a 7M-GTE car.

Replace the fan clutch if it spins freely by hand when cold ($150-300), or convert to an electric fan setup with a quality controller ($300-600).

Ensure the fan shroud is intact and properly sealed to the radiator, gaps allow air to bypass the radiator core.

Cost mentioned in fix

$300-600$150-300

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// More Supra (A70) problems

Other known issues

Common Engine, 7M-GTE (Turbo)

Head Gasket Failure

The head gasket blows, allowing coolant into the combustion chambers and/or oil passages. White smoke from the exhaust, coolant loss without visible external leak, overheating under boost, milky oil on the filler cap, and bubbles in the coolant overflow tank. In severe cases, hydrolock (coolant filling a cylinder and bending a connecting rod on startup).

Critical Engine, 7M-GTE (Turbo)

Low Oil Pressure at Idle

Oil pressure drops below 10 psi at hot idle. The factory oil pressure warning light may flicker or illuminate at idle, particularly in traffic on hot days. The engine may develop bearing noise (deep knocking from the bottom end).

Common Engine, 7M-GTE (Turbo)

CT-26 Turbo Failure

Loss of boost pressure, excessive oil smoke (blue/grey) on startup or deceleration, whistling or grinding noises from the turbo, and oil in the intercooler piping.

Common Engine, 7M-GTE (Turbo)

Fan Clutch Wear

The engine runs hotter than normal, particularly at low speeds and idle. The cooling fan doesn't seem to pull much air through the radiator.

Critical Engine, 7M-GE (Naturally Aspirated)

Head Gasket Failure (Less Common)

Common Transmission

W58 Synchro Wear

Crunching or grinding when shifting into 2nd or 3rd gear, particularly when cold or during quick shifts. The synchros may improve slightly once the gearbox oil is warm.

View all 17 Supra (A70) problems