1986-1993 / Coupe / Japan
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Submit an updateThe 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).
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).
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.
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.
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.
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.