Niagara Gazette — •••
MARK FROM PHILADELPHIA: My indicator gauge on my ‘04 Mazda Tribute does not indicate that the engine is hot. However, it smells hot after I’ve been driving for a short time, and I see a little smoke coming from under the hood. What would be causing this?
TOM: The smell could be a result of a coolant leak, oil leak, or transmission fluid leak burning on a hot exhaust. In short, lots of things could cause this condition. Get it into a shop and have it checked out immediately.
Cars tell us when they have a problem; we just have to pay attention. Mark’s car is expressing symptoms of a leak. So how do we track it down?
• Check fluid levels: Smoke from under the hood is a key symptom. First, check all the fluid levels (oil, transmission, coolant, brake fluid, and power steering fluid). If any of the fluids are dramatically low, start the diagnostics there. Get the car up on a lift and check underneath for engine oil, coolant, or transmission oil leakage. The leak may evade you. If this is the case, there are lots of tests you can perform to track down the source.
• Cooling system test: The best way to find a leak in the cooling system is a pressure test. The goal of the test is to force a leak at the weakest point in the system. Air pressure is applied to the cooling system with an air pump or regulated source (make sure to keep pressure below 14 PSI to avoid causing more damage). If there’s a leak in the radiator, water pump, gasket, or a hose, it will show up under pressure. Sometimes a system will lose pressure but it will not display an external leak. This tells you that there’s probably a leak internally, such as a blown head gasket or cracked/warped cylinder head.