I recently had my check engine light come on, I took my truck to a shop and was told that my Electronic Thermostat had failed and it needed to be replaced. So I had it replaced and on the way home it started to overheat, so I called the shop and was told to bring it back because the new thermostat was probable defective. After the second replacement, it still is overheating. After the second time at the shop, I figured that the cooling system has a air bubble in it. I burped the system and nothing, it is still overheating. I then had the system flushed and pressurized and ended up with the same results... Overheating. I am wondering, is the second thermostat stuck closed?