Grand prix heat off and on also, drinking coolant?

20

Asked by Jan 21, 2016 at 09:55 PM about the 2002 Pontiac Grand Prix SE

Question type: Maintenance & Repair

02 grand prix 250k miles. Really weird situation here, what it does is the
gauge will act normally and produce heat normally. All of a sudden it flies
up and down slowly almost overheats but doesnt. Then the gauge will
come back down all the while me having absolutely no heat. What ive done
before is add coolant (dexcool) And it will stop, it will produce heat, and act
normally for about two weeks. Now ive noticed no physical spiils on the
ground and the oil isnt milky. It needs changed but isnt milky. any ideas???
im at a loss here...

3 Answers

41,025

Wildly fluctuating coolant temperatures would indicate to me that you have a bad thermostat.

1 out of 1 people think this is helpful.
83,435

When it starts the fluxuations is when it is running low on coolant, the most probable cause is a blown headgasket especially with that kind of mileage. I would recommend performing a block test, that will confirm that exhaust gases are present in the cooling system.

1 out of 1 people think this is helpful.
59,175

Since this is a SE model I'm assuming you have the 3.1L V6. They blow head gaskets. But before you condemn the motor, at 250,000 miles the head gaskets should have been done already, long ago. With the engine cold pressure test the cooling system. You may have a seeping hose, water pump, radiator, or heater core. The cooling system should hold 15 PSI for a minimum of 15 minutes. If not it's leaking somewhere. Also pressure test the radiator cap. It may not be holding pressure. That can cause a "sneaky" leak as well. HTH. -Jim

Your Answer

Add photo

Related Questions

  • 1998 grand prix over heating 5 answers

    the top radiator hose gets hot but the bottom one does not. no heat in the car and i have replaced the thermostat. coolant level is good.

    1998 Pontiac Grand Prix

    -

    Maintenance & Repair

  • 2006 Grand Prix Overheating and Low Cabin Heat? 42 answers

    I have a 2006 Grand Prix Gt 3.8 Supercharged. I was gettin glow cabin heat so I flushed out the rad and heater core added new Dexcool mixed 50/50 and the engine started overheating and still low cabin...

    2006 Pontiac Grand Prix GT

    -

    Maintenance & Repair

  • Pontiac grand prix se 3.1 coolant problems 10 answers

    Ok so I have a 2002 pontiac grand prix se 3.1. I'm kinda lost at what to do since I'm not a car guy, I do have mechanical abilities as I have fixed a couple things already on vehicles. But I was w...

    2002 Pontiac Grand Prix SE

    -

    Maintenance & Repair

  • 2004 Pontiac Grand Prix Ask me any questions 33 answers

    I have totally replaced and rebuilt this car. I have experienced some major obstacles and solved them. I have experience with this year model Grand Prix. I may be of some help to others.

    2004 Pontiac Grand Prix GTP

    -

    Maintenance & Repair

  • 2004 durmax drinking coolant 5 answers

    I just bought a 2004 durmax coolant light keeps saying low coolant there no leak I keep putting coolant in it runs fine does not over heat .

    Maintenance & Repair

Grand Prix

Looking for a Used Grand Prix in your area?

CarGurus has 3,715 nationwide Grand Prix listings starting at $879.

ZIP:

Search Pontiac Grand Prix Questions

UK Questions

Are you a UK consumer? CarGurus now has a discussion forum in the UK.

Pontiac Grand Prix Experts

#1 Js08016
Js08016
Reputation 3,890
#2 Tom Demyan
Tom Demyan
Reputation 2,580
#3 munron
munron
Reputation 2,060
View All

Related Models For Sale

Used Chevrolet Impala
904 Great Deals out of 35,274 listings starting at $1,700
Used Pontiac Bonneville
8 Great Deals out of 646 listings starting at $1,375
Used Chevrolet Monte Carlo
18 Great Deals out of 1,692 listings starting at $2,491
Used Pontiac Grand Am
1,661 listings starting at $1,298
Used Chevrolet Malibu
1,129 Great Deals out of 82,876 listings starting at $2,328
Used Chevrolet Camaro
400 Great Deals out of 40,630 listings starting at $3,500
Used Ford Mustang
533 Great Deals out of 42,736 listings starting at $1,699
Used Buick Regal
150 Great Deals out of 11,603 listings starting at $1,850
Used Jeep Grand Cherokee
903 Great Deals out of 66,333 listings starting at $1,500
Used Nissan Maxima
381 Great Deals out of 24,382 listings starting at $999
Used Nissan Altima
1,073 Great Deals out of 82,589 listings starting at $1,988

Used Cars For Sale

2008 Pontiac Grand Prix For Sale
13 Great Deals out of 473 listings starting at $900
2007 Pontiac Grand Prix For Sale
518 listings starting at $2,995
2006 Pontiac Grand Prix For Sale
3 Great Deals out of 630 listings starting at $2,000
2005 Pontiac Grand Prix For Sale
439 listings starting at $5,900