My 1999 firebird recently had the heater hose blow, which made everything else go crazy. I ended up changing the water pump as well as the timing belt. After that, I've encountered a problem accelerating at higher speeds. The engine kinda bogs like its shaking slightly. I had it scanned and it told me that my coil to the 6th cylinder is misfiring, get that changed, boom check engine light gone. Now here's where it gets weird, I still have the bogging problem at higher speeds and temperature. The computer also read that the ECT was defective, but could that be the problem exactly? I changed the fuel pump, pcv valve, got an oil change, fuel filter.