1993 Mazda RX-7

What can fail

Engine heat breaks down the fuel hose material, causing leaks. Removing and reinstalling these hoses during service also increases leak risk.

What the fix does

A cooling fan control unit is added to run the fan after engine shutdown when coolant is hot. Fuel hoses are replaced with improved versions.

What can fail

The radiator cap's pressure relief valve opens at too high a pressure, causing excessive coolant temperature and leaks. Leaked coolant can concentrate on the engine and ignite if it reaches the hot exhaust manifold.

What the fix does

Replace the radiator cap and filler cap body. For vehicles with significant leakage, also replace the water pump bearing housing, coolant level sensor, upper radiator hose, thermostat gasket, and engine-mounted water hoses.

What can fail

The radiator cap's pressure relief valve opens at too high a pressure, allowing coolant to overheat beyond safe limits. This can cause coolant to leak and collect on top of the engine.

What the fix does

Dealers will replace the radiator cap, filler cap, and filler cap body with new parts designed to release pressure correctly. Affected cooling system components will be inspected and replaced if damaged by overheating.