Engine Cooling problem
2000 Chevy Malibu 6 cyl Front Wheel Drive Automatic 168000 miles
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my car has gotten hotter than normal a few times but has been fine. It has been running hot the last few days so I changed thethermostat and it corrected the problem. Today while i was driving I noticed a little bit of steam coming out of the hood but it went away then about 10 miles later it got really hot and died. started steaming. when I started it again it was hard to start but when it did it sounded almost like a rod knocking but went away if revved up. It would get real hot in a matter of seconds when started. Is this a head gasket or something worse