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Q: Coolant temperatures seem too high but my coolant levels are fine

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I just replaced my radiator. Hit a bucket and cracked a small hole in it. The new one is in and I've been watching my coolant temp like a hawk. After 15 minutes of driving my temperature will spike to 212. Doesn't seem normal for it to get that hot but I never paid attention to the gauge before the accident so I dont know what's normal for my car. Nothing else was damaged apart from the radiator and the fan works fine. I did have to recharge my a/c, but it lost its charge after a few days. Checked all attachments, nothing is loose. On a hot hot day last week it hit 227 waiting at a red light. I haven't driven longer than 30 minutes since putting in the new radiator and have a two hour drive coming up this weekend. And I check my coolant level every morning. Haven't had to fill it at all. What's making it run so hot?

My car has 110000 miles.
My car has an automatic transmission.

Hey there. There are many newer cars that require you to prime the radiator system anytime you add coolant and especially when you install a new one.

The reason for this is that air gets trapped in the coolant lines and will cause an overheating situation. However, a broken water pump might also be causing this problem.

Anytime you have an accident that damages the cooling system, it’s recommended to start from scratch. Replace the radiator, inspect the pump, replace the belts, and prime the coolant system to ensure no air is trapped in the system. A worse case scenario is that you have a blown head gasket that is causing the overheating issue. If you can, start from scratch or contact a local ASE certified mechanic to help you diagnose the overheating problem.

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