I have a 2000 deville with 101k miles on it when i start the car it idles high and makes a whistling sound for about 10 seconds and then the noise stops and the idle comes down only code is p0420 could the cat cause that problem, also for the past two weeks my right passenger window wouldnt go down i think using wrong cig lighter caused problem ,checked fuses all ok ,when i cleared the codes it started working how could this be?