Bad clutch symptoms include slipping clutch, low acceleration on high rpm, lost pick, increased gas mileage and overall significant power loss. Excessive play in clutch pedal also indicates worn clutch. As far as coils are concerned; weak spark, missing, rough idle, power loss, hesitation when revving up from a dead stop. But no definitive sign exists. You have to check things manually because these symptoms are shared by other possible faults as well such as bad fuel injectors, bad or wrong spark plugs, weak fuel pump or clogged fuel filter etc.