Chevrolet TrailBlazer:

Car heat while AC is on

You are not logged in.

# 1  7/22/2014 11:25 AM

abdoonabil
Member
Registered: 6/23/2014
Posts: 10

Car heat while AC is on

Hi Sir, Please I have a very strange issue. My trailblazer 2003 is getting hot more than normal (Medium) 
so I went to a mechanic and he said you have to clean the radiator and change thermostat. So I cleaned it and change the thermostat then it keeps getting hot when I drive for 20 or 30 Minutes. Then he said maybe we need to change the water pump. So we change it and I put coolant in too. Then it's still getting hot while I drive more than 30 Min. Finally I noticed something, that when I turn off my air conditioning the car heat is starting to go toward medium again (by the way I'm in Kuwait and temperature in day light is around 44 C  )

So what is your suggestion about this issue.

Thanks in advance

Offline

 

# 2  7/22/2014 7:58 PM

TechHelp2
Administrator
Registered: 11/24/2009
Posts: 1299

Re: Car heat while AC is on

There are some things you can try.

One reason this could be happening is that you have an air pocket in the engine and you need to get the air out. If there is a bleeder valve on the thermostat housing or the top of the engine, open this first until coolant comes out of the hole. If there is no bleeder valve then go to step two.

Jack up the front of the truck and support with jack stands or use ramps. Take the radiator cap off the radiator (When it is cold) and start the engine. Let it run until the thermostat opens and continue to watch the coolant level to make sure it stays to the rim of the radiator. The purpose for this is to force the air to the front of the vehicle and to the radiator to escape. After a while replace the cap and level the coolant recovery tank and take the truck for a test drive and see what the results are.

Next step is to perform the steps in a service bulletin No.: 04-06-02-005
Date: July 27, 2004.This explains the reduced air flow across the radiator and preheated air from stopped or slow moving driving conditions from traffic congestion that may result in normally higher engine coolant operating temperatures as indicated by the temperature gage.

The service bulletin explains the procedure to reprogram the PCM with an updated software calibration. This needs to be done at a GM dealership and the use of the Tech2 scan tool. This new calibration will cause the PCM to command small amounts of additional fan engagement to control engine coolant temperatures and gauge readings closer to a customer perception of normal.

Try these suggestions and get back to me with your results when you can.


realworldautomotive.com
car and truck information like nowhere else

Offline

 

# 3  7/26/2014 6:52 AM

abdoonabil
Member
Registered: 6/23/2014
Posts: 10

Re: Car heat while AC is on

Thank you. I tried the first solution, but the second one is very hard to do. So if there is any thing else I can check
and how about the fan clutch how to test it?

Offline

 

# 4  7/26/2014 12:50 PM

TechHelp2
Administrator
Registered: 11/24/2009
Posts: 1299

Re: Car heat while AC is on

The fan should make excessive noise at engine start up (cold) and slowly go away as the engine warms up.

The fan should reengage (make louder noise) between the temperatures of 85C to 96 C with the engine running about 2000 RPM with the A/C turned on. The temperature of the engine then should drop about 3C to 10C. Do not continue the test if the engine temp exceeds 96 C.

Check the fan by turning the fan by hand (engine off and cold) and it should have resistance to it. If it continues to turn freely after you spin the fan then the clutch is bad. It may turn freely when the engine is warm so do this check cold.

See if there is silicone leakage around the fan clutch, if the fan shows signs of leakage (excessive) and turns freely the fan is bad. Some leakage may appear and the fan can still work normal.

Move the fan at the blade tip latterly (in and out not spinning) you should not have any play more that 1/4 of an inch. (below 1/4 of an inch is normal.

I know there is probably no dealer or scan tool but to truly check the entire electronic system a scanner should be used. If you need extra help other what I have supplied you I will send the entire check list for you. The items I just sent you are from that list. These are the simple tests you can do without a scan tool.

Let me know about your progress when you can.


realworldautomotive.com
car and truck information like nowhere else

Offline

 

# 5  8/4/2014 9:51 AM

abdoonabil
Member
Registered: 6/23/2014
Posts: 10

Re: Car heat while AC is on

Dear sir, I couldn't check very well the fan re engagement, but there is no leak , and the fan is not turning more than one round when I move it with my hand.

Nowadays the engine has gotten hot after 15 Min. I noticed that if I stopped and put gear on P or N and then pressed on the gas pedal to make the RPM go higher it starts to go down on the dash gauge after two to three min.
(My car is not for the Gulf it's american and my temp gauge is [100,210,240])

When I drive with it for 15 min, it goes past the 210 F with two dashes maybe three
then I stopped and put gear on P and press gas pedal to make RPM go higher
it went down again with one dash on the gauge.

Then I shutdown the engine to let it get rest
by the way when I tried to start the engine with this heat on engine
it was crank but not start. Really the GM dealer is very hard on me
but I can go to a shop and have a scan tool put on the vehicle, that is what I will tell him.

Thanks for your support

Offline

 

# 6  8/4/2014 2:51 PM

TechHelp2
Administrator
Registered: 11/24/2009
Posts: 1299

Re: Car heat while AC is on

Have your mechanic diagnosis the cooling fan clutch relay circuit to make sure the relay for the fan is operating the fan properly.

Also have him check the high pressure switch on the Air conditioner high pressure hose. If this is faulty it will not turn on the fan when the temperature of the coolant rises when the Air conditioner is turned on.

This can be checked with a scan tool.

Get back to me with your results when you can


realworldautomotive.com
car and truck information like nowhere else

Offline

 

# 7  8/6/2014 6:33 AM

abdoonabil
Member
Registered: 6/23/2014
Posts: 10

Re: Car heat while AC is on

Dear Sir,

Fan fuse is ok , Relay is tested by replacing with the low beam Relay and it's still working
but i don't know what to do really now
and by the way , there is a water tank feed the radiator with water
when the car got heat the water in this tank got very hot and may reach boiling

so please suggest any solution if you can please
tell me what to scan with the scan tool
send me the list you said about it if it's possible please

thanks in advance

Offline

 

# 8  8/6/2014 2:31 PM

TechHelp2
Administrator
Registered: 11/24/2009
Posts: 1299

Re: Car heat while AC is on

If the fan is working there are two things it could be, either you have a clogged radiator or you still have air in the cooling system and it needs to be removed.

You can do this by putting the truck on an incline like ramps or jack stands. Run the engine with the radiator cap off and keep the radiator full at all times. Sometimes this could take a few hours so be patient and monitor the coolant level in the radiator for the entire time.

Also if you have a thermometer you can check the temperature of the engine by sticking it into the coolant at the radiator (where the cap is) and compare the reading of the thermometer to the temperature of the gage inside the truck and you can also use a scan tool to monitor the temperature of the engine and compare all three readings they should be very close in temperature.

The operating temperature of and engine when the fans turn on should be about 220 degrees (about 100 centigrade).

Without seeing the truck running for myself it is hard to be precise with a diagnosis.

Try this again to see if you can get some air out of the engine and let me know your results when you can.


realworldautomotive.com
car and truck information like nowhere else

Offline

 

# 9  8/10/2014 3:17 PM

abdoonabil
Member
Registered: 6/23/2014
Posts: 10

Re: Car heat while AC is on

Sir , can you please tell me if this is normal. Fan clutch will work when temp reach 210 but it only work for seconds and off again. Then after 10 min. temp will exceeded 210 by 2 dashes and clutch will work again for 10 or 20 second then off again but the car temp didn't go down. Then heat will continue but clutch is dead. So I turned off the car and waited till the temp to go down.

Is the fan clutch supposed to still be working till the temp goes down low or is this normal for clutch or is there another issue.

I changed clutch yesterday and it's carved on it 'made in USA'
Or maybe it's fake

Thank you for quick response

Offline

 

# 10  8/10/2014 5:51 PM

TechHelp2
Administrator
Registered: 11/24/2009
Posts: 1299

Re: Car heat while AC is on

From what you are telling me about the fan operation it would appear to be operating normally. The fluid in the clutch thins out when temperature rises and then is controlled by the PCM

If this is what your temperature gage looks like then it appears that your cooling system may be operating properly.

That is why I said before you need a scan tool to check out things like fan speed, engine temperature, air conditioner pressures switch operation and so on.

The fan is designed to go on at 220 degrees (about 104 centigrade) , each notch is 5 degrees (3 centigrade) your using the reference of the 210 degree mark and two notches after that would make it 220 degrees which is the normal temperature the engine is expected to maintain. If the temperature is only going just the two marks past 210 degrees then it appears the system is performing properly.
As long as the temperature maintains those readings and does not exceed the temperature set by the manufacturer then the fan operation is considered normal.
The PCM commands the cooling fan to 100% under the following conditions:
•    Engine coolant temperature exceeds approximately 129°C (264°F).
•    The transmission oil temperature exceeds approximately 151°C (304°F).
•    A/C refrigerant pressure exceeds 1655 kPa (240 psi).
•    When certain DTC's set. These include P0116, P0117, P0118, P0125, P1481, P1482, and P1484.

If you have any further questions please ask we are here to help you.

https://www.realworldautomotive.com/forums/uploads/thumbs/174_94953683.gif


realworldautomotive.com
car and truck information like nowhere else

Offline

 
E-mail Page
Print Page
Save or Share Information
ALLDATAdiy.com is the leading source of factory diagnostic & repair information specific to your car.

Powered by PunBB
Copyright © 2007-  RealWorldAutomotive.com

Save or Share Automotive Information
Custom Search