* A cracked engine block: This is the worst-case scenario. A crack near a coolant passage and hose connection would leak coolant. This is a major repair, potentially requiring engine replacement.
* A bad freeze plug (core plug): These are metal plugs that seal coolant passages in the engine block. They can corrode and fail, leading to leaks. They are relatively inexpensive to replace, but labor costs could be significant depending on accessibility.
* A damaged or corroded threaded port: Some coolant hoses connect to threaded ports on the engine block. Corrosion or damage to these ports can cause leaks. This might be repairable by replacing a damaged fitting, or potentially requiring a more extensive repair if the block is damaged.
* A leaking hose connection: While you mention "next to" the hose housing, the leak might actually *be* from a poorly seated or damaged hose clamp on a coolant hose. This is the cheapest and easiest fix. Inspect the hose clamps carefully.
To determine the exact cause:
1. Clean the area thoroughly: Wash away all dirt and grime around the suspected leak to clearly see the source.
2. Inspect carefully: Look for cracks in the block, corrosion around ports or freeze plugs, and any signs of coolant escaping from specific points.
3. Pressure test the cooling system: A mechanic can pressure test the cooling system to pinpoint the leak. This is crucial for identifying a leak in a hard-to-see location.
Without visually inspecting the engine, it's impossible to say definitively what's causing the leak. You'll need a mechanic or at least a thorough visual inspection to properly diagnose and repair the problem. Ignoring a coolant leak can lead to overheating and serious engine damage.
