Over Heating and Radiator questions


Asked by Jan 31, 2014 at 02:16 PM about the 2003 Chevrolet Blazer LS 4-Door RWD

Question type: Maintenance & Repair

My car is overheating really quickly, I've seen no signs of a leak but I do have no heat for my air conditioning. Can these two things be related? the radiator fluid is just dumping into the overfill and looks boiled off inside the radiator. Do I need to flush it now too?

6 Answers


Have you changed out your thermostat yet? Do that first. Probably your problem and the cheapest part to start with.......

1 of 1 people found this helpful.

I replaced the thermostat 2 weeks ago, I also flushed the radiator out at that time too

2 of 2 people found this helpful.

The only other component that will usually cause a vehicle to overheat is the water pump. If your air conditioner is not putting out cool air, your compressor is probably bad. In your description you said, "no heat for my air conditioning". Did you mean to say that when you turn on your blower fan for heat you have no heat? If so, that would mean that your heater core is plugged. Have you dumped a ton of stop leak into your radiator before? I did that once, and it all settled in my heater core and plugged it solid.......

1 of 1 people found this helpful.

The blower fan, however I've never put any stop leak in it


You have air in the system or blown head gasket. Go to advance or autozone and buy a air bleed kit for the cooling system. This will get all the air out with no mess. If it still overheats you probably have a blown head gasket.

1 of 1 people found this helpful.

or he might have a plugged radiator or heater core, how many miles are on it? last time the water pump was replaced? could have no fins left on it. how did you flush the cooling system? how is the fans working? are they electric? do they have two speeds if they're electric or if its mechanical, turn the car off and gently shake the fan, if it moves around easily the clutch went bad, also a good time to replace the water pump. usually on those cars the blend door gets stuck on the cool position and won't go down for the heat does your ac work well and the heat suck? hhmmm theres so much to know when your working on cars.

1 of 1 people found this helpful.

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