Replacement directions for Heater core

2008 CHEVROLET IMPALA
150,000 MILES • 3.5L • V6 • FWD • AUTOMATIC
Avatar
ALPHAHAWG
  • MEMBER
  • 1 POST
I need directions to replace heater core.
Sep 27, 2016 at 8:44 AM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Hi,

The heater core is located on the inside of the vehicle under the dash. It's a little bit of a job but if you follow the directions, you can do it.

First, here is a link that shows how it's done in general. Use this as a guide.

https://www.2carpros.com/articles/replace-heater-core

____________________________________________________________

Here are directions specific to your vehicle. The two attached pics are the actual directions and an exploded view of the heater unit.

2008 Chevrolet Impala V6-3.5L
Heater Core Replacement
Vehicle Heating and Air Conditioning Heater Core Service and Repair Removal and Replacement Heater Core Replacement
HEATER CORE REPLACEMENT
Heater Core Replacement


pic 1



pic 2

_________________________________________

I hope this helps. Let me know if you have other questions.

Take care and God Bless,

Joe
Feb 12, 2021 at 1:15 PM
Avatar
POPOLITA
  • MEMBER
  • 1 POST
How to get to and remove the heater core in my car listed above. It's leaking a lot of antifreeze!
Feb 19, 2021 at 1:50 PM (Merged)
Advertisement
Avatar
DANNY L
  • CERTIFIED EXPERT
  • 5,648 POSTS
Hello, I'm Danny.

Here is the information you requested. Here is a tutorial to get you started on how to replace a heater core:

https://www.2carpros.com/articles/replace-heater-core

I've attached picture steps below on how to remove and replace the heater core on your car. Hope this helps and thanks for using 2CarPros.


Feb 19, 2021 at 1:50 PM (Merged)
Avatar
LARRYJR6720
  • MEMBER
  • 2 POSTS
I have a 2005 chevy impala im trying to take the housing off so i can remove the heater core. i have the bolt off the houseing but it still will not come off. what am i missing? can u help
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
BLUELIGHTNIN6
  • CERTIFIED EXPERT
  • 16,542 POSTS
REMOVAL:
Disconnect the negative battery cable.
If equipped with a 3.1L engine, remove the air cleaner and duct assembly.
If equipped with a 3.8L engine, remove the fuel injector sight shield by performing the following procedures:
Clean the area around the oil filler cap/tube assembly location.
Rotate the oil filler cap/tube assembly counterclockwise from the valve cover.
Lift the fuel injector sight shield up at the front and slide it from the rear engine bracket.
Reinstall the oil filler cap/tube assembly in the valve cover.

CAUTION
Before draining the cooling system, allow the engine to cool to relieve the systems internal pressure and to avoid scalding coolant.





Drain the cooling system by performing the following procedure:
Raise and safely support the front of the vehicle.
Remove and clean the coolant recovery tank.
Place a 2 gallon pan under the radiator to catch the coolant.
At the bottom of the radiator, open the drain valve and drain the coolant to a level lower than the heater core.
Remove the radiator cap and open the air bleed screw (2-3 turns) located on top of the thermostat housing.
After sufficient coolant has been drained from the system, close the drain valve.

CAUTION
Engine coolant is a hazardous waste; it should be stored for reuse or submitted for recycling. NEVER dispose of it by dumping it into the environment.





Disconnect and plug the heater hoses at the heater core.
If equipped, remove the lower center console by removing or disconnecting the following:


Cigarette lighter
Automatic transaxle shift handle
Upper console trim plate from the front floor console by unsnapping it
Electrical connectors from the upper console trim plate and remove the trim plate
CD storage compartment from the front floor console by unsnapping it
Raise the front floor console armrest and remove the compartment mat
Console-to-chassis bolts and screws
Electrical connectors from the console and remove the console from the vehicle


Remove the lower instrument panel lower compartment by removing or disconnecting the following:


Lower right instrument panel insulator
Compartment-to-panel bolts and screws, from under the instrument panel compartment
Instrument panel compartment door screws and the door
Instrument panel compartment screws and plastic clips; then slide the compartment from the instrument panel
Electrical connector from the compartment
Ashtray and bracket, if necessary
Lower heater duct
Heater core cover and discard the cover seals Heater core mounting clip and bracket
Heater core



INSTALLATION:
Install and connect the following:


Heater core in the vehicle
Heater core mounting clip and bracket
New seals on the heater core cover
Heater core cover and torque the bolts to 13 inch lbs. (1.5 Nm)
Lower heater duct, if removed
Ashtray and bracket, if removed


Install the lower instrument panel lower by installing or connecting the following:


Electrical connector to the compartment
Slide the compartment into the instrument panel; then, secure it with screws and plastic clips Instrument panel compartment door and screws Compartment-to-panel bolts and screws, located under the instrument panel compartment
Lower right instrument panel insulator


If equipped, install the lower center console install or connect the following:


Console in the vehicle and connect the electrical connectors
Console-to-chassis bolts and screws, tighten in sequence beginning at the front right and continue in a clockwise order to 106 inch lbs. (12 Nm) Armrest compartment mat and lower the front floor console armrest C/D storage compartment into the front floor console
Electrical connectors to the upper console trim plate and snap the trim plate onto the console
Automatic transaxle shift handle and the cigarette lighter
Heater hoses to the heater core and secure with the clamps


Refill the cooling system by performing the following procedure:
Close the radiator drain valve.
If the air bleed screws (located at the top of the thermostat housing) is closed, open it by turning it 2-3 turns.
Slowly add coolant until it reaches the radiator neck.
Wait for 2 minutes and recheck the coolant level; then, add more coolant if necessary.
Fill the coolant reservoir to the COLD mark.
Close the air bleed screw.
WARNING
Do not over-tighten the air bleed screw for it is made of brass.

Install the radiator cap and make sure that the arrows align with the overflow tube.



If equipped with a 3.8L engine, install the fuel injector sight shield by performing the following procedures:
Remove the oil filler cap/tube assembly from the valve cover.
Slide the fuel injector sight shield into the rear engine bracket and lower it into place.
Reinstall the oil filler cap/tube assembly in the valve cover. Twist it clockwise to lock the detent on the tube into the notch in the valve cover.



If equipped with a 3.1L engine, install the air cleaner and duct assembly.
Connect the negative battery cable.








Thanks for using 2CarPros.com!
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
LARRYJR6720
  • MEMBER
  • 2 POSTS
how do i go about removing the heater duct. can i just removed the bottom of the duct and remove the heater core
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
BLUELIGHTNIN6
  • CERTIFIED EXPERT
  • 16,542 POSTS
The above procedures is the best way and recommended way of removing and replacing your vehicle's heater core.. You will need to remove the instrument panel lower trim panel and remove the retaining screw and bolts to remove duct.
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
BRIAN61969
  • MEMBER
  • 2 POSTS
how do you remove a heater core on a 2004 Impala SS 3.8l v6. the heater core is leaking. Well I really need to know how to take the heater core out.
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
STRAILER
  • CERTIFIED EXPERT
  • 53,854 POSTS
Hey BRIAN,

Doing a heater core is a big job but you can tackle it if you just stick to it. Here are some instructions and a diagram or two to help you through the job.

Remove the fuel injector sight shield.

Drain the cooling system. Refer to Draining and Filling Cooling System in Cooling System.
Use J 38185 in order to position aside the heater hose inlet and outlet clamps at the heater core.
Disconnect the inlet and outlet heater hose from the heater core.
Remove the RH Instrument Panel Closeout/Insulator panel.
Remove the LH Instrument Panel Closeout/Insulator panel
Remove the floor carpet.
Remove the rear floor air outlet duct from the holes in the floor reinforcement.
Disconnect the rear floor air outlet duct from the heater air outlet cover.
Remove the rear floor air outlet duct.
Remove the heater air outlet cover screws (2).
Remove the heater air outlet cover heat stakes (1) with a small chisel.
Remove the heater air outlet cover from the HVAC module assembly.
Remove the heater core cover screws (2).
Remove the heater core cover heat stakes (1) with a small chisel.
Remove the heater core cover from the HVAC module assembly.
Remove the heater core from the HVAC module assembly.
Remove the heater core foam seal (1) from the HVAC module assembly.

Please let us know happens so it will help others. check out the diagram (Below)

Best, Ken
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
REVERAGE
  • MEMBER
  • 4 POSTS
The heat in my car is not working consistently. It will blow nice hot air one minute and then get cold and the temperature gauge will rise until it red lines. Then the air will get hot again and the temperature gauge will go back down to normal. I have flushed the radiator and entire cooling system, changed the thermostat, changed the coolant temperature sensor and back flushed the heater core. The problem is still present. There is no leak from the heater core on the floor board nor does the windshield fog up and no smell of anti freeze. I guess my question is could my heater core still be bad?
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
STEVE W.
  • CERTIFIED EXPERT
  • 15,113 POSTS
That description sounds like there is air in the system or you have a failing head gasket that is putting combustion gases into the system and causing pockets of air that way. It is also possible the cap is faulty but that usually will show as low coolant.
Are you removing the bleed screws on the engine while filling with coolant?

Feb 19, 2021 at 1:50 PM (Merged)
Avatar
REVERAGE
  • MEMBER
  • 4 POSTS
No. I am not aware of any bleeding screws. Where would they be located?
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
STEVE W.
  • CERTIFIED EXPERT
  • 15,113 POSTS
There should be one on each end of the engine. One on top of the upper radiator fitting over the thermostat housing, the other in above the water pump. 7MM that looks like a pipe plug.
Another option is to see if your local part store has a vacu-fill system you can rent. With that you drain the coolant down, then apply enough vacuum to pull out all the air, then it sucks the coolant into the system and you have no air pockets.
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
REVERAGE
  • MEMBER
  • 4 POSTS
I opened them as the car was running and I was adding more coolant. It seems to be working. I will keep opening them over the next few days to get all the air out, but as of now the heat is working and temperature gauge is staying normal. Once I have the air out and it works consistently if the problem arises again it is probably a failing head gasket. I hope not. Thanks for your help.
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
STEVE W.
  • CERTIFIED EXPERT
  • 15,113 POSTS
That should take care of the problem. The 3.1 and 3.4 both have a bad habit of holding air in the block. Once you get them "burped" they settle down. It is why I have the vacuum unit it pulls all the air out you do not need play with the bleeders. Many engine these days have bleeder valves.
Keep us informed please.
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
REVERAGE
  • MEMBER
  • 4 POSTS
Will do. Thanks again.
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
ASEMASTER6371
  • CERTIFIED EXPERT
  • 52,796 POSTS
Good morning

Just to add what Steve has posted, do not open the bleeders with the engine running. it will draw air into the system. only open the bleeders while filling.

Roy
Feb 19, 2021 at 1:50 PM (Merged)
Avatar
SLIMBOB2932
  • MEMBER
  • 1 POST
How do I replace this heater core. I need step by step instructions. Can't get to it from the engine compartment.

Thank you,
Slimbob2932
Feb 19, 2021 at 1:51 PM (Merged)
Avatar
HMAC300
  • CERTIFIED EXPERT
  • 48,601 POSTS
make sure it is antifreeze and not water if water check to make sure drain hose is going through firewall an drubber above cabin filter is draining correctly or not partially off. see pics for instructions.
Feb 19, 2021 at 1:51 PM (Merged)
Avatar
ALAN WHITE2
  • MEMBER
  • 1 POST
Heater core is leaking anti-freeze into passenger cabin. The car is too old and in too bad of shape to replace.

How do I "by-pass" the core to stop the leak?
Feb 19, 2021 at 1:51 PM (Merged)
Avatar
JOHNNYT73
  • CERTIFIED EXPERT
  • 924 POSTS
Locate the two coolant hoses running into the firewall that go into the heater core. You can attempt to cut them loop them together with a 'U" shaped hose or pipe to bypass the heater core.
Feb 19, 2021 at 1:51 PM (Merged)
Avatar
DOLPHIN838
  • MEMBER
  • 1 POST
heater core replacement in 2002 chevy impala What's the easiest way to replace the heater core?
Feb 19, 2021 at 1:51 PM (Merged)
Avatar
KASEKENNY
  • CERTIFIED EXPERT
  • 18,907 POSTS
Unfortunately there is no short cut for this vehicle. I am attaching below the process from the manual on how to replace this.

Let us know if you have questions. Thanks
Feb 19, 2021 at 1:51 PM (Merged)