i have a 2000 gmc yukon (new body style) and i have a few lights on in the dash.....1st my abs and e-brake lights are on. i think they came on because it was time to change the brake pads in the rear but after changing them the lights are still on. am i wrong or do they have to be reset? if so how to reset them?.....2nd my service engine soon light is on. i took it to an auto parts store so they could use a code reader to check it. the code reader said that there was a misfire in ignition system but i just changed the plugs and wires about 6mths ago so what else could it be? so symptoms are when cold the rms are wayyy low when idling and has been so low that it shuts off. also when cold i shift from park to drive or reverse and it hesitates causing a sudden jerk. could some of this be the cause of a faulty fuel pump?.....things ive done are flowmaster muffler, installed a fuel saver that connects to the MAF sensor, and also knocked out the waffle cone thingy that was inside the MAF sensor. any suggestions are greatly appreciated.