Car blows heat in summer, not in winter. Car overheats in winter, not in summer.

Matthew Robinson

Asked by Apr 27, 2016 at 07:37 PM about the 2005 Pontiac Grand Am SE

Question type: Maintenance & Repair

I have a V6 05 Grand Am that has a very strange problem. I cant seem to
get an answer from anyone. In the winter my car will overheat, but then
drop back down to mid level. When its blowing heat its staying around mid
level on temp gauge, when its blowing cold it heats up to the point that
sometimes it overheats. In the summer, the car heats to mid fast and
sometimes goes a hair over mid but never overheats. It also blows heat like
crazy. This winter I had a coolant explosion (coolant everywhere) and the
shop replaced the water pump. I have replaced the thermostat as well. Any
idea's what this could be as even with the new water pump I am getting the
same results.

1 Answer


I am suspicious of a head gasket problem, when a head gasket blows it starts using coolant, when the coolant get low enough the heat stops working. I would have a shop perform a block check test to confirm a head gasket.

Your Answer

Add photo

Related Questions

Search Pontiac Grand Am Questions

Pontiac Grand Am Experts

#1 tenspeed
Reputation 7,080
#2 John Saffrahn
John Saffrahn
Reputation 1,480
#3 Tom Demyan
Tom Demyan
Reputation 1,240
View All

Related Models For Sale

Used Pontiac Grand Prix"
27 Great Deals out of 4,392 listings starting at $1,972
Used Chevrolet Impala"
939 Great Deals out of 35,889 listings starting at $700
Used Pontiac G6"
148 Great Deals out of 5,688 listings starting at $999
Used Ford Mustang"
728 Great Deals out of 41,499 listings starting at $900
Used Dodge Charger"
684 Great Deals out of 30,346 listings starting at $1,995
Used Pontiac GTO"
8 Great Deals out of 515 listings starting at $5,995
Used Chevrolet Malibu"
1,181 Great Deals out of 72,977 listings starting at $695
Used Pontiac Bonneville"
861 listings starting at $1,450
Used Honda Civic"
1,173 Great Deals out of 59,023 listings starting at $1,300
Used Nissan Altima"
1,492 Great Deals out of 88,167 listings starting at $1,195
Used Honda Accord"
1,308 Great Deals out of 78,748 listings starting at $1,395
Used Jeep Grand Cherokee"
1,201 Great Deals out of 74,214 listings starting at $1,500