The age of that car and what you have done so far? Yep. Sounds like the water pump. If it isn't leaking fluid thru the bleed hole, then it's slowing down....new water pump time.
the water pump will still circulate water even if the seal leaks , , are the fans coming on when it gets hot ? what does the exhaust look like , pull the oil fill cap and look on the bottom what do you see ?
No leaks in bleed hole I'm hopingbits just water pump SMH
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