Would spark plugs cause my car to run hot. 1997 Chevy blazer. Changed them. runs hotter then normal. could the do that car.?

Spark plugs themselves would not cause your car to run hot. However, if the spark plugs were not properly installed, they could cause the engine to misfire, which could lead to overheating. If you are experiencing overheating issues after changing the spark plugs, it is important to have a qualified mechanic inspect the vehicle and identify the cause.