I have a 97 1500 burb with a 5.7L/350 motor. I recently replaced the lower intake manifold because it was leaking and caused my engine to overheat. The truck overheated for about an hour. I believe I might've damaged the engine. It has about 162,000 miles on it. Now when I apply the gas pedal it just feels heavy. I have to literally slam it to get er to move. When i try cranking er up she sounds kinda weird. A "service engine soon" sign appears too. Theres abnormal clicking noise and the truck vibrates more than normal. I feel warm air coming from the truck too but the thermostat is alright. This never happened before. What could be wrong?