My car is overheating — what should I do?
The short answer
If the temperature gauge is climbing into the red or steam is appearing, pull over safely and shut the engine off — continued driving can warp the cylinder head within minutes and turn a $200 repair into an engine replacement. Let it cool 30+ minutes before even opening the hood, and never open a hot radiator cap.
Reviewed by Joe Zeiter
Service Director · Grote service team · Updated July 17, 2026
Likely causes, ranked
Coolant loss from a leak
A failed hose, water pump seal, radiator seam, or heater line lets coolant escape until there isn’t enough to carry heat away. The most common overheating cause — and usually visible as puddles or crust trails once on a lift.
Stuck thermostat
A thermostat stuck closed blocks coolant from reaching the radiator at all — classic rapid overheating shortly after startup. An inexpensive part with an expensive failure mode.
Cooling fan failure
If the car only overheats in traffic or drive-through lines but cools on the highway, the electric fan or its relay is the prime suspect — airflow at speed masks the failure.
Failing water pump or head gasket
A worn pump can’t circulate coolant; a breached head gasket lets combustion pressurize the cooling system. The head gasket is often the *result* of a prior overheat — which is exactly why stopping early matters.
What to do right now
- 1
Pull over and shut the engine off as soon as it’s safe. Heat blasting on full can buy a mile or two in a pinch, but stopping is the real answer.
- 2
Wait 30+ minutes before opening the hood; never open the radiator or reservoir cap while hot — pressurized coolant scalds.
- 3
If coolant is visibly low and you have the correct type (or water in an emergency), top off and drive gently and directly to a shop — or better, call for a tow. We can arrange one: (779) 888-5000.
What it typically costs
Diagnosed early: hoses and thermostats commonly $180–$420, radiators $600–$1,200. Driven hot: warped heads and head gaskets start around $1,500–$3,000 and climb toward engine replacement. The tow is always the bargain.
Our diagnosis fee goes toward the repair.
Related questions
Can I just keep adding coolant and drive it?
You’re refilling a leak on a timer you can’t see. It works until the day the loss rate wins — usually on the highway — and one bad overheat undoes years of careful maintenance. A pressure test finds the leak for less than a summer’s worth of coolant jugs.
Why does my car only overheat in traffic?
At speed, ram air cools the radiator for free; sitting still, the electric fan has to do it. Overheats-in-traffic-only is the textbook signature of a failed fan, fan relay, or clogged radiator core — a targeted, findable problem.
What actually fixes it
If it turns out to need real work, this is what usually does it — with pricing published up front, so there are no surprises.
Prefer we reach out?
We respond within the hour during business hours — usually faster.
This guide describes common patterns, not a diagnosis of your specific vehicle — that takes an inspection. If your symptom is marked urgent, treat it as urgent. When in doubt, stop driving and call (779) 888-5000.
Stop wondering. Start knowing.
A proper diagnosis costs less than a wrong guess — and ours is applied to the repair.
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