2001 Pontiac Grand Am • 3.4L V6 Automatic • 175,000 miles

How can you tell if the coolant reservoir is bad? There are no holes or actual leaks coming from it from what we can see. It looks somewhat warped and the reservoir cap is stripped. I replaced the reservoir cap once before but it ended up becoming stripped just like the last one.
June 2, 2014.

You need to answer a question for me. Is the reservoir the only place to add coolant? In other words, there is no cap on the radiator? Is this a reservoir that is pressurized or just an overflow bottle that collects coolant then returns it to the motor when needed?

I have no radiator cap. Just the reservoir.I believe it is pressurized.

Jun 3, 2014.
Okay, the reservoir on your vehicle needs to be able to pressurize. If the cap is stripped, that can't happen. As a result, you may lose coolant or the engine could overheat. Can you tell me if the cap or the tank is stripped? Since this is the 2nd cap, it sounds like the threads on the reservoir may be bad.