Pontiac grand am 2005 v6: thermostat or head gasket?

Asked by Aug 08, 2017 at 11:16 PM about the 2005 Pontiac Grand Am

Question type: Maintenance & Repair

I was driving my grand am for about 45 minutes. I didn't notice any issues,
but when I got into town and hit a couple of stop signs, it started acting like
it was out of gas. It was sputtering, not really wanting to drive unless I
really gassed it. The "low coolant" light came on, then disappeared, then
the "service engine soon" light came on. I parked the car and let it sit.
When I checked the basics I could see that the water was completely gone
from my water reservoir (I think that's what it's called... the thing that holds
my water for the radiator). The oil was a little low but it was not discolored
at all. Today I tried to put water back in the tank and run the car again (just
idling, not driving) and the water started spurting out of the overflow tube.
The car never overheated when I first had problems. I didn't run it long
enough to see if it would overheat today. The water kind of scared me. I
have zero idea what's wrong. My dad was thinking the thermostat or the
water pump but the guy at the part store said it sounded like a head
gasket. The oil isn't milky. It has been sitting for 2 days since the car first
acted up.

Thank you for your help!

5 Answers

there is an idle switch that engages the gas when your foot pushes the pedal. this basically tells the engine to idle, and so on. to mee this sounds like the first sign, and ALL other symptoms would arise from that main issue. If it was driving normally, and after stop and go at stop signs in stopped working properly, sounds to my like it is either a transmission issue or a simple idle switch.

Oh, gosh... more options! It didn't idle high but it was cutting out like crazy. There was no water there. It all shot out the overflow, but my car didn't overheat. I think I was lucky to be so close to home when it started cutting out. Is there anything else I can look for to cut out other options?

I noticed that the exhaust was puttering and the smoke was kind of white. It smelled really rich, and when I gassed it there was really thick white smoke.


you know the radiator has to tube one up and down.the down tube connect with hose that is going to water pump and water pump circulation the water inside the engine after that when the water be hot there is two hoses going inside the dash to the heater core and after that the water when get high temperatures the thermostat open and the water going out to the radiator for cooling and back again to the engine...so I am sorry for long explain but ..for my experience head gasket cause misfire p0300.second not all blown head gasket first shows mixed of oil and water.if you want make sure about that just make oil change and you can see all the oil about color..if there is no signs for that you need to check the water pump . You can pull the thermostat out and connect the thermostat housing to the engine if still same problems that's mean the water still in the radiator and water pump not circular and the pressure push the water out from radiator


it's a bad head gasket , look on the bottom of the oil fill cap and tell me what you see

Your Answer

Grand Am

Looking for a Used Grand Am in your area?

CarGurus has 37 nationwide Grand Am listings and the tools to find you a great deal.

Postal Code:

Pontiac Grand Am Experts

  • #1
  • #2
    John Saffrahn
  • #3
    Tom Demyan
View All

Related Models For Sale

Used Pontiac Grand Prix
6 Great Deals out of 72 listings starting at $1,600
Used Pontiac G6
5 Great Deals out of 147 listings starting at $1,982
Used Chevrolet Impala
114 Great Deals out of 1,115 listings starting at $996
Used Pontiac GTO
4 listings starting at $13,900
Used Ford Mustang
15 Great Deals out of 1,158 listings starting at $4,500
Used Toyota Camry
108 Great Deals out of 2,542 listings starting at $2,000
Used Dodge Charger
78 Great Deals out of 802 listings starting at $2,298
Used Honda Accord
89 Great Deals out of 1,118 listings starting at $750
Used Honda Civic
353 Great Deals out of 3,920 listings starting at $1,495
Used Ford F-150
658 Great Deals out of 13,648 listings starting at $3,000
Used Chevrolet Monte Carlo
17 listings starting at $2,188

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.