Heater core replacement

Tiny
BABYEYES85
  • 2001 PONTIAC GRAND PRIX

GT 6 cyl Front Wheel Drive Automatic - My heater core is bad in my 2001 Pontiac Grand AM GT.I have another one to replace it with. But everyone is telling me that it is REALLY HARD to change. I dont have the money to put it is the shop so I was going to let my brother do it. How hard is it to change it? I love this site

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Monday, February 1st, 2010 AT 8:55 PM

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Tiny
2CARPROS KEN
  • ADMIN
  • 12,123 POSTS

It's not too bad to do in this car here is a guide and some diagrams so you can get the job done. This guide will give you an idea of what you are in for when doing the job.

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

You will need to vacuum down and recharge the air conditioner system

https://www.2carpros.com/articles/re-charge-an-air-conditioner-system

Here are step by step diagrams (below)

Please let us know if you need anything else to get the problem fixed.

Cheers, Ken

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Friday, November 17th, 2017 AT 2:08 PM
Tiny
RACERMARK1978
  • 2000 PONTIAC GRAND PRIX

Heater problem
2000 Pontiac Grand Prix 6 cyl Two Wheel Drive Automatic 110000 miles

would welcome detailed advice on how to replace heater core in above car which has 3.8 motor. I am a good home mechanic
thank you

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Friday, November 17th, 2017 AT 2:09 PM (Merged)
Tiny
BLUELIGHTNIN6
  • EXPERT
  • 16,912 POSTS

1. Disconnect the negative battery cable.
2. Remove the cosmetic/acoustic engine cover, as equipped.
3. Remove the air cleaner and duct assembly.
4. Drain the engine coolant into a suitable container.
5. On the 3.4L (VIN X) engine, remove the throttle body and the throttle body tube to which it mounts.
6. Disconnect both heater hoses from the heater core. On some vehicles, accessing the firewall side heater hoses can be a challenge due to limited working space. In addition, some vehicles equipped with the 3.1L engine may have quick-connect fittings on the hose, requiring special tool J 38723 Heater Line Quick Connect Separator, or equivalent.
7. Remove the lower center console, if equipped. Additional information may be found in the Control Panel service instructions, found in this section.
8. Remove both left and right underdash sound insulator panels.
9. Disconnect the lower heater duct.
10. Remove the heater core cover. The sealer usually should be discarded and replaced with new sealer. Evaluate the condition of the existing sealer and the availability of new sealer.
11. Locate and remove the heater core mounting clip and bracket and remove the heater core from the vehicle. Use care as it will likely have coolant inside and could drip onto the rugs or seats.
12. Installation is the reverse of the removal process. After refilling the cooling system, bleed out the air and check for leaks as outlined in of this guide.
13. Connect the negative battery cable.

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Friday, November 17th, 2017 AT 2:09 PM (Merged)
Tiny
JANESADLER
  • 2007 PONTIAC GRAND PRIX

Do you have to remove the dashboard to replace the heater core

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Friday, November 17th, 2017 AT 2:09 PM (Merged)
Tiny
ASEMASTER6371
  • EXPERT
  • 25,476 POSTS

According to the instructions I sent you, the dash does not have to be removed/

Roy

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Friday, November 17th, 2017 AT 2:09 PM (Merged)
Tiny
BOSSDODJ
  • 2002 PONTIAC GRAND PRIX

2002 Pontiac Grand Prix 6 cyl Two Wheel Drive

how do I replace the heater core in 2002 grand prix and unhook the passenger side air bag

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Friday, November 17th, 2017 AT 2:09 PM (Merged)
Tiny
AIMLADY@HOTMAIL.COM
  • MEMBER

Yeah, this is a good question. I have the same problem. I have the $40.00 heater core part in hand, but cannot find anyone to do the extensive labor without charging an arm and a leg or being afraid to disconnect all the electrical and air bags in order to take out the entire dash board to get the heater core. Someone please help us! Thank you!

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Friday, November 17th, 2017 AT 2:09 PM (Merged)
Tiny
JOE FLORES
  • 2004 PONTIAC GRAND PRIX

Heater problem
2004 Pontiac Grand Prix 6 cyl Front Wheel Drive Automatic 120000 miles

hi im tring to change the heater core on my car but I need help I never change one thank you

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
BOILER
  • 2004 PONTIAC GRAND PRIX

Heater problem
2004 Pontiac Grand Prix 6 cyl Front Wheel Drive Automatic 150000 miles

I have a 2004 pontiac grand prix with all the signs of a leaking heater core. Windows are steamed up and I smell antifreeze, and its leaking on the floor board. How hard is this to replace? Do I need to remove the whole dash? Any special tools? Any concern dealing with the air bags? Thanks for any info!

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
ERNEST CLARK
  • EXPERT
  • 1,753 POSTS

This is a very involved process. I'd suggest purchasing a "Single-Vehicle" subscription to an on-line repair database such as: "Alldata" or "Mitchell 1".

This will give you some pictographic repair procedures to refer to, as well as coming in handy on your next project.

Here's the R&R for you heater core:

Before servicing the vehicle, refer to the Precautions Section.

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

To install:

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.

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
DRIVER3528
  • 1999 PONTIAC GRAND PRIX
  • 6 CYL
  • 2WD
  • AUTOMATIC
  • 140,000 MILES

Trying to remove heater core in a 1999 Pontiac Grand Prix. And replace.

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
JACOBANDNICKOLAS
  • EXPERT
  • 68,474 POSTS

I believe it calls for around 4 hours.

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
BIGDADDY1993
  • 1993 PONTIAC GRAND PRIX
  • 6 CYL
  • FWD
  • AUTOMATIC

How do u find and replace a heater core on a 1993 grand pirx

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
WRENCHTECH
  • EXPERT
  • 20,934 POSTS

https://www.2carpros.com/images/external/42188668.gif

REMOVE OR DISCONNECT

1. Negative battery cable.
2. Drain coolant system.
3. Upper weatherstrip from body.
4. Upper secondary cowl.
5. Lower secondary cowl upper nut.
6. Heater hoses from core.
7. Blow out residual coolant from core using shop air. This will prevent coolant leakage into the passenger compartment.
8. Lower right sound insulator panel.
9. Rear seat duct adapter.
10. Heater floor duct.
11. Lower left sound insulator panel.
12. Core cover screws and cover.
13. Core retaining bolt and core.

INSTALL OR CONNECT

1. Core and attaching bolt.
2. Core cover and attaching screws.
3. Lower left sound insulator panel.
4. Heater floor duct.
5. Rear seat duct adapter.
6. Lower right sound insulator panel.
7. Heater hoses to core and tighten clamps to 1.7 Nm (15 lb in) .
8. Upper nut securing lower secondary cowl panel.
9. Upper secondary cowl panel.
10. Refill coolant to proper level.

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
RODNEYHEYWARD
  • 1977 PONTIAC GRAND PRIX
  • 122,054 MILES

How do I replace my heater core

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
JDL
  • EXPERT
  • 16,334 POSTS

Found this info.

1977 Grand Prix
WITHOUT AIR CONDITIONING
Disconnect the negative battery terminal.
Drain the cooling system, disconnect the heater hoses, and plug the core tubes.
Remove the screws and nuts from the heater module on the engine side.
Remove the glove box to gain access to, and remove, the defroster duct screw, and the control cables.
Loosen the sealer and remove the case assembly and core from inside the vehicle.
Installation is the reverse of removal. Use a strip caulk type sealer when installing the case assembly to the firewall.

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
2CARPROS-ARCHIVES
  • 2006 PONTIAC GRAND PRIX
  • 12,500 MILES

Can you provide some instructions on how to replace heater core?

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
JACOBANDNICKOLAS
  • EXPERT
  • 68,474 POSTS

This is a big project. As a result, I recommend getting a good repair manual with step by step instructions and pictures to help identify parts. For me to explain this via the internet allows too much room for error.

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
2CARPROS-ARCHIVES
  • 2006 PONTIAC GRAND PRIX
  • 90,000 MILES

I'm having a problem with the heat blowing warm to cold air won't get hot I've changed the thermostat and bled the system but one of the lower hose coming from heater core is cold most of the time while the rest are piping hot that same hose gets a little warm when I give car rpms but can't get heat to stay hot what do I do

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Friday, November 17th, 2017 AT 2:10 PM (Merged)
Tiny
JACOBANDNICKOLAS
  • EXPERT
  • 68,474 POSTS

Since one of the heater hoses is staying cold, I recommend flushing the heater core.

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Friday, November 17th, 2017 AT 2:10 PM (Merged)

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