Q: Had blown spark plug on my engine. The spark plug was replaced a few times and the engine is shaking really bad.

Hi there. If the spark plug is constantly burning up, then check the coil and see if it has a proper ground. The coil wire could be producing too much resistance making the coil overheat and send too much current to the spark plug making it burn up. The ignition timing could be off causing the engine to shake and not run properly making the spark plug burn out faster than normal. I recommend replacing all of the spark plugs with the OEM specified spark plugs and retesting the situation. If you need further assistance with your engine spark plugs failing, then seek out a professional, such as one from Your Mechanic, to help you.