I am running a stage 3 sds and have an e-manage to tune with. I have 440's (rc). I recently have been noticing that my car inconsistantly wants to stall out at idle and sometimes upon accelerating from closed thottle stays lean until after I wait for about 5 seconds or play with the trottle a little bit. I thought it might be with the blow off valve (new ripp) but after cleaning found that it didn't fix it. Around idle my vac is around 19-21 in gear and 22-25 in nuetral or part (automatic). Would a failing O2 cause it? Any ideas what it could be?