My 03 is overheating. So far I have flushed out the coolant. I do not know if my radiator is clogged. When I removed the old coolant I did not have any clumps or anything everything looked normal. I removed the T-stat and ran the car without the T-stat and engine was still overheating. Both fans are working. Also in the inside the air is freezing even when the heater is "on". Could it be the water pump or is the radiator called.

The car has 84K miles.

 

First, did you look up under the car to see if any debris is in front of the radiator (actually it is the A/C condensor). These cars act as vacuum cleaners and plastic bags will overheat them.

If you don't see anything, you should still "backflush" your radiator with low pressure air or water, by flowing from inside the engine compartment towards the front. If you remove the top bracket, you can see between the coils.

I am confused, your car is overheating, but you get no heat inside it?

What temperatures are you seeing? 236 F is normal temperature.

 

I forgot to mention that I have cleaned the radiator I took off the bracket and cleaned both the radiator and the A/C Condensor. The other day the car got all the way past 265 and the engine degraded so I shut the car off. I ended up having to rent a Uhaul flatbed and I towed my car to my house in the rain.

 

You didn't fill out your profile or say what year your car is.

Here is 2002 Shop Manual checks:

2002 Chevrolet Corvette


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Engine Overheating
Step
Action
Yes
No

1
Inspect for a missing or damaged radiator upper or lower baffle and/or radiator air deflector.

Is the baffle and/or deflector missing or damaged?
Go to Step 8
Go to Step 2

2
Inspect for a loss of coolant.

Is there a loss of coolant?
Go to Step 3
Go to Step 4

3
Fill the system to the specified level. Refer to Loss of Coolant .

Does the engine overheat?
Go to Step 4
System OK

4
Inspect for low coolant protection.

Is the coolant to the correct concentration?
Go to Step 5
Go to Step 8

5
Inspect for a loss of cooling system pressure.

Is there a loss of system pressure?
Go to Step 8
Go to Step 6

6
Inspect for a faulty engine coolant temperature (ECT) sensor. Refer to DTC P0117 , DTC P0118 , or DTC P0125 in Engine Controls - 5.7L.

Is the sensor operating properly?
Go to Step 7
Go to Step 8

7
Inspect for a cracked coolant surge tank or a leaking hose.

Is the coolant surge tank cracked or is the hose leaking?
Go to Step 8
Go to Step 13

8
Repair or install new parts as necessary, then retest.

Does the engine overheat?
Go to Step 9
System OK

9
Inspect for incorrect drive belt tension.

Is the belt tension correct?
Go to Step 10
Go to Step 8

10
Remove the water pump. Refer to Water Pump Replacement .
Inspect for a damaged water pump driveshaft.
Is the water pump driveshaft damaged or is the seal leaking?
Go to Step 8
Go to Step 11

11
Inspect for obstructed radiator air flow or bent radiator fins.

Is the radiator air flow obstructed?
Go to Step 8
Go to Step 12

12
Inspect for blocked cooling system passages.

Are the cooling system passages blocked?
Go to Step 8
Go to Step 13

13
Inspect for inoperative cooling fans. Refer to Cooling Fan Inoperative .

Are the cooling fans and the motors operating correctly?
Go to Step 14
Go to Step 8

14
Inspect the thermostat. Refer to Thermostat Diagnosis .

Is the thermostat stuck in the closed position?
Go to Step 15
Go to Step 16

15
Replace the thermostat. Refer to Thermostat Replacement .

Does the engine overheat?
Go to Step 16
System OK

16
Inspect the radiator cooling capacity.

Is the proper sized radiator being used on the vehicle?
Go to Step 3
Go to Step 17

17
Consult the current parts catalog and replace the radiator. Refer to Radiator Replacement .

Is the repair complete?
System OK
--



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It's possible the sensor has failed...

 

That is step # 6 in the above checkout.

 

Provided you have the system full of coolant/water, and air is out........
If you have removed the t stat, then the coolant is free to flow ( provided the water pump is functioning and there is no blockage). Have you checked the upper radiator hose to ensure the coolant is circulating?

 

How do I check if the upper radiator hose is to check if the coolant is circulating.

 

ahhh....by placing your hand on it. If coolant is not circulating, the hose will remain cold. The engine needs to be at operating temp.

 

The hose is cold when running and temp still rising past 220

 

Sounds like no circulation from blockage or water pump failure. I would think you would have other issues if the belt was loose, but it's worth checking.

 

Nevermind I drove it around the neighborhood for 5 min and checked the hose then and the hose was hot!!. Both fans were running.

 

I know, but thanks for pointing that out. ...and it's usually one of the most over looked parts to check when this symptom occurs.

 

Have you pulled up your codes? Did it list any of the temperature sensor codes?

Still no heat in the car?

 

there are no dtc codes. There is no heat in the car.

 

bump

 

Sounds like you have a heater core problem......

 

are you going to fill out your sig?

 

help please

 

Did you go through the diagnosis fault tree from the shop manual above? Are you having a problem (either understanding it or getting a bad result) with one of the steps?

Were you down a lot of coolant when (after) you initially overheated?

Do you have any leaks now, when you fill up the coolant and run the engine?

When you overheat now does water come out of overflow? How high did your temperature get driving around the neighborhood?

Does your pressure cap hold pressure? When you get to 220 F, if you slightly open your cap (DO NOT OPEN ALL THE WAY) is there a pressure relief?

You now have an antifreeze mixture in the car, right?

Where do you live? What is the outside temperature?

IF your temperature sensor is correct, it sounds like your water pump is not working (and circulating coolant through your heater). Is your belt okay? Does your lower water hose get hot? One of the steps is to remove your water pump and inspect it. It is hard for me to believe that the pump could be bad and not pumping, maybe the shaft is broken?