This tool provides general guidance — not professional mechanical advice. Always have a qualified mechanic inspect your vehicle before making any repair decisions.
#1 Most Likely
Sweet or syrupy smell from engine
Typical Cost
$150 – $3,246
Radiator hose replacement typically costs $150–$300. Radiator replacement typically costs $300–$900. Head gasket replacement typically costs $2,475–$3,246 per industry repair data (2024). Urgency reflects worst-case cause (coolant loss leading to overheating). NEEDS_SOURCE — verify against published repair data. Prices vary by vehicle make and region.
Wide range because the exact repair depends on what's causing the symptom.
- Leaking radiator hose or clamp
- Cracked or leaking radiator
- Failing water pump seal
- Internal heater core leak
- Head gasket allowing coolant into the combustion chamber
A sweet or syrupy smell near the engine may indicate a coolant leak. Ethylene glycol — the primary ingredient in most coolants — has a distinctively sweet odor. Even a small coolant leak can lead to overheating if coolant level drops below a critical threshold. In the worst case, continued driving with a coolant leak may cause head gasket failure or engine seizure.
What a mechanic will check
A mechanic will likely pressure-test the cooling system to locate the leak source, inspect the radiator, hoses, heater core, and water pump for seepage, and check coolant level and condition. A combustion leak test may be performed to rule out an internal head gasket leak.
What to say to your mechanic
“I smell something sweet or syrupy near my engine. Can you pressure-test my cooling system and inspect for coolant leaks? I want to know where the coolant may be coming from and whether I am at risk of overheating.”
Script based on industry repair procedures