2008 Mazda5. Est. 90K miles or so. Wife called today that the temp gauge was "all the way to H". Mostly stayed "in the middle" during the 45 minute drive. When accelerating, creeps up toward the H. When slowing down, it cools down, or when maintaining speed.
Checked the overflow, it's at the correct level. When she pulled in from driving 45 minutes, I threw some towels over the radiator cap and popped it loose. Coolant was cold, and just enough pressure to make it trickle overflow. Not like the blast of hot coolant you would expect. I started the engine back up with the rad cap off and the coolant level went down. I'm hoping this means the pump is pumping.
Radiator Cap, thermostat, water pump. The first two are an easy replacement. The latter not so much.
Thoughts? I'm thinking thermostat is stuck closed.
Checked the overflow, it's at the correct level. When she pulled in from driving 45 minutes, I threw some towels over the radiator cap and popped it loose. Coolant was cold, and just enough pressure to make it trickle overflow. Not like the blast of hot coolant you would expect. I started the engine back up with the rad cap off and the coolant level went down. I'm hoping this means the pump is pumping.
Radiator Cap, thermostat, water pump. The first two are an easy replacement. The latter not so much.
Thoughts? I'm thinking thermostat is stuck closed.
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