also have a look at ur idle up motor AAC Valve air bypass valve located under throttle body, usually a faulty coolant temp sensor will cause high idles, usually a vaccum leak will cause problems constantly rough idle, intercooler piping popped off will cause black smoke out the exhaust n stalling, n leakin injectors will cause smell out of exhaust of unburnt fuel and rough idle. they could be leakin over night foulin the plugs, take ur plugs out check them clean them start it n see if improves, blow through AAC valve see if opening. lots of things look around for the obvasious first