Ok, i have been havin a problem for some time with my msp. 2 cel codes, lean bank 1 and misfire cylinder 1. On cold start it dies a couple times before staying running and puffs a cloud of whiteish gray smoke. Smells rich, runs ok until it reaches operating temp then it misses hesitates and sputters on take off and wot. Change the plugs atleast once every two weeks if not 2. When i take them out theyre a bit whiteish on the tip and black carbon around the electrode and threads. Any help would be greatly appreciated. Checked for vacuum leaks and cannot find anything, cleaned egr and iac