No, you need to use one that has the same specs as the old one. You should be able to find one online with the model number that's on the old one, or perhaps contacting the manufacturer for the part number. Circuits are designed with certain specs, that if altered, could cause poor performance (not as much power as before) or burn something else out. Digi-key is a good place to look for electronic parts too.
You may want to try and clean the connector on the accessory. The copper corrosion (green stuff) can get down in that as well. Think back to the old NES, there was a cleaner pad for the game and for the console. A small wooden toothpick soaked in alcohol can get in there and clean the connection if your careful not to break the toothpick (Its very humid where I live, this happens all the time and I got tired of buying new iphone cables).
Knocking is usually caused by slow ignition or because ignitions is too soon or too late. One of the easiest things to check is to make sure the gap on your spark plugs is at manufacture's specs. Depending on the mileage, another issue you can have is your camshaft and crankshaft are out of time. This happens when the timing belt (which is made of rubber) has more slack than the tentioner can take up. One way to check if its a head gasket, look for oil in your coolant or water in your oil (wierd spots in coolant or a white-ish looking sluge or goo in oil).