- All
- Product Name
- Product Keyword
- Product Model
- Product Summary
- Product Description
- Multi Field Search
Views: 0 Author: Site Editor Publish Time: 2020-05-14 Origin: Site
It may be something as simple as a low level of coolant in the system or more complicated as rusted water passages in the engine block itself.
Most often than not, the reasons vary around a few common issues:
Low coolant level
Bad radiator cap
Clogged up radiator
Worn coolant
Bad thermostat
Failing cooling fan
Failed water pump
Worn-out or damaged water pump drive belt
Normally, a vehicle engine needs to operate at a temperature of 195 to 220F (91 to 104C). This helps to:
improve engine combustion
lower emissions
extend components service life
improve fuel efficiency
But this normal operating temperature can be upset through a sudden failure. The temperature may climb out of control in a minute and destroy your engine.
So, if your engine is overheating, don't wait to find out the cause.
Here, you'll find some of the most common - and not so common - reasons for your car engine to overheat.
We start with some general conditions under which you may be experiencing engine overheating.
This condition-based diagnostic guide is followed by a general procedure you can use to check your vehicle's cooling system, if necessary. Then, you'll see a list of cooling system components (many of which appear in the condition-based section) and how those components can fail.
All together, these procedures will help you fix your engine overheating sooner, and at a lower cost.
I. Engine Overheating Condition-Based Diagnostic
My Engine Doesn't Overheat But Runs Hotter Than Normal
My Engine Overheats Unpredictably
My Engine Overheats While Idling or Moving Slowly in Traffic
My Engine Overheats While Moving on the Road
My Engine Overheats Soon After It Starts
II. Inspecting the Cooling System
III. Checking for Potential Faulty Components
IV. Using a Cooling System Check Strategy
A vehicle engine may only overheat under certain operating conditions. You may notice the temperature rising as soon as you start the engine, while sorting through heavy traffic, while driving on the highway. However, the temperature may rise erratically.
Here is a list of common conditions under which your engine may be experiencing overheating, or near overheating, and some of the most common sources of trouble.
Sometimes a fault in the cooling system may cause the engine temperature to almost reach the red zone all the time. Here's a list of components you may want to check first:
Bad radiator cap
Collapsed lower radiator hose
Bad cooling fan
Restricted radiator or water passages in the engine block
Bad thermostat
Restricted air flow through the radiator
Engines can overheat without following a clear pattern. The temperature will rise suddenly at any time, which makes it harder to diagnose. Still here are a few components that may cause the temperature to rise suddenly:
Low coolant level
Bad thermostat
Bad radiator cap
Failing cooling fan
Temperature sender or circuit malfunction
Engine speed can sometimes be a factor in engine operating temperature, if a cooling system component becomes faulty. You may want to check for:
Low coolant level
Restricted air flow through the radiator
Faulty radiator fan
Leaking head gasket
Faulty water pump
Bad radiator cap
Bad thermostat
Clogging exhaust system
You may notice your car engine only begins to overheat while driving at the highway. This symptom may indicate poor coolant flow. Several components in the system may be at fault:
Bad thermostat
Collapsed lower radiator hose
Bad radiator cap
Bad water pump impeller
Radiator or engine water passages filled with rust
Poor air flow through the radiator
Failing thermostat
A car engine needs a few minutes to reach operating temperature. However, if you notice the temperature gauge reaching the red zone a few seconds after you start the engine, your engine may not actually be overheating.
Usually, this points to a malfunctioning temperature sender, or a problem in the circuit.
Check for a bad temperature sender
Check for an electrical short in the circuit
This is a good place to start, the cooling system. Often, an overheating condition is the caused of a neglected system. You may spot a bad radiator hose, notice a noisy water pump or a loose drive belt, just by making a visual inspection. Here are a few things you might want to check:
Low or Worn Out Coolant:
If you've neglected the cooling system for quite some time, it might be running low on fluid or the coolant mixture has worn out.
Antifreeze looses its preventive properties over time. That's why car manufacturers recommend replacing the coolant every two or five years, for example, depending on the type of coolant you're using.
Check your owner's manual or repair service manual for the recommended change interval for your particular vehicle model. If you don't have your manual, buy an aftermarket service manual for your make, model, and year. They are inexpensive and full of maintenance and repair how-tos you'll use frequently on your car. Besides, the manual will pay for itself on your first repair or maintenance job.
Coolant Leak:
On the other hand, if you find yourself adding coolant to the system on a regular basis, suspect a leak.
Check for wet spots:
under your car
around the radiator and heater core
radiator and heater hoses
engine block
water pump
thermostat housing
Your car repair manual will help you locate the different cooling system components.
If you can't seem to find the leak source, it's possible the engine has an internal leak. Take in your car for a cooling system pressure test to locate the leak, if necessary.
The following video can also help you check the cooling system in your car.
Bad components in the cooling system and engine can also lead to overheating problems.
Inspect the radiator and heater core for collapsed or damaged hoses that may be restricting coolant flow.
Check for poor air flow through the radiator and A/C condenser. Look for debris and bugs covering the grill on the radiator and condenser — the radiator-like device mounted in front of the radiator. A blocked radiator or condenser will cause the engine to overheat. Also, bent fins will block air flow through the radiator.
Inspect the radiator cap (unless, of course, it's too hot to touch). A failing or loose cap will cause the coolant's boiling point to fall and allow coolant to leak. Replace it if the cap or its seal show signs of wear or damage. Have the radiator cap pressure tested, if necessary.
A thermostat stuck in the closed position, blocking the flow of coolant between the engine and radiator will cause the engine to overheat too. With the engine running and unable to carry heat away, heat will practically cook and melt the engine, if you fail to notice. Check the thermostat yourself following the simple procedure described in this article related to car thermostat problems.
If you haven't serviced the cooling system at the recommended interval, rust may be clogging up radiator passages, affecting water pump performance, choking water jackets inside the engine, and causing the temperature to rise. In mild cases of rust buildup, you may have a chance to save the radiator by flushing the cooling system and adding fresh coolant.
On the other hand, if engine overheating started right after you replaced the old coolant, did you forget to bleed the system? On modern vehicles—especially those with low hood lines—the cooling system tends to form air pockets whenever you refill it with coolant.
Air pockets create hot spots that cause overheating. And they'll crack the engine if the temperature rises well beyond its ideal range. Check your repair manual for the proper procedure to purge the cooling system in your vehicle.