Who told you the t-stat needed replacement? If it was a reputable shop, then chances are you need it. If you're going to replace the t-stat then do the pump @ the same time. You'll experience symptoms such as your car is displaying. It was also log codes as well. Someone w a scanner can read them for you and let you know. These cars are notorious for the said parts failing and its usually at the most inconvenient times. Do a little research on the forums and you'll see the posts about this exact same issue. There's a lot of them too. If you're fairly handy at diy tasks this is more than doable if you have a lift. Good luck.
Edit: didn't even realize it was you delon. How you been man?
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