I don’t know if any of what I’m going to describe is normal for cars so please forgive me for my ignorance. Newbie lang ako eh..

The previous owner of my car obviously replaced the radiator with a smaller, local one that looks substandard. I’m not sure how old this radiator is. But he says as long as you always put water in it, ok lang. The car has never overheated on him.

So far he’s been correct. I religiously put water and the temp is always at the middle of the gauge. I’ve always add water when the engine is cold and the radiator inlet is too small for me to see if the water is rushing, confirming if the water pump is indeed working.

However, I’ve been noticed hot water gushing from the hose leading to the reservoir so I understand this to be normal. Just a few minutes ago I decided to try something that I’ve never done before: uncap the radiator after driving, while the engine is supposedly at mid temp.

I encountered resistance when trying to remove the radiator cap; I guess there’s adequate pressure and the cap is working right?

Hot water didn’t erupt when I uncapped the radiator but very soon after, as in a few seconds later, the fan switched on and the water started to bubble from the inlet, like it was overheating or about to do so. I scrambled to switch the engine off.

Do any of these symptoms point to a failing water pump or an inadequate radiator? Is my temp gauge accurate?