How to Troubleshoot the Cooling System in a Toyota Tacoma

Understand your cooling system's function to help diagnose problems. In short, antifreeze collects heat as it passes through the engine and releases heat when it goes in the radiator. Cooling devices usually circulate coolant, contain it or control its temperature. Troubleshoot the cooling system in a Toyota Tacoma by inspecting cooling devices. The following steps apply to most model years.

Difficulty:

Moderate

Instructions

1. • 1

     Inspect the water pump for leaks. Your water pump keeps antifreeze moving through the engine, radiator and heater core. A faint coolant smell or spots of antifreeze under your Tacoma when parked for a short time are signs of a faulty water pump.

   • 2

     Check hoses for cracks, collapses, leaks or dryness. This includes upper and lower radiator hoses, heater and bypass hoses and manifold coolant hoses. The upper hoses, for instance, measure about 2 inches wide and carry antifreeze between the radiator and engine. A damaged hose causes cooling system problems.

   • 3

     Examine your antifreeze level. Low coolant leads to overheating. With low levels, put long-life antifreeze that meets Toyota vehicle specifications in the coolant tank reservoir. This applies to the four-cylinder 2 TR-FE and six-cylinder 1-GR FE engines.

   • 4

     Remove the antifreeze and flush the system to explore cooling problems. Make sure to dispose of coolant properly because the sweet smell of it attracts animals and small children. Ingesting the toxic liquid can be fatal.

   • 5

     Look at the radiator cap to see if it is faulty. A damaged cap could contain corrosion. Get a mechanic to use a pressure tester or an adapter to examine the cap's pressure rating and operation. Replace a defective cap promptly.

   • 6

     Wash and rinse the front of your radiator. Dirt, rocks, leaves and other debris suck into the vents of your radiator when driving which causes overheating. Use a soft nylon brush, soapy water and a water hose to clean your radiator front.

   • 7

     Test the thermostat to see if it is sticking. Identify a stuck thermostat with constant low temperature readings or peaks between high and normal temperatures. Usually you can find your thermostat residing inside the housing on the engine side of the upper radiator hose.