When idling, my cars rpm is about 650. Every once in a while i kinda chugs, like a break in the smooth idle. Also when it does this there is a mechanical noise/chug/rattle, hard to explain. I can get this sound if i almost stall the car when letting out the clutch without enough throttle. I find that if i keep the rpm around 750 i dont get this intermittent lump in my idle. Anyone know what im talking about. Im due in on monday to replace my bose stacker, and the dealer said he would up the warm idle to 700-750. TIA

 

If you dont have cams . I would start checking for vacuum leaks . I found one leak on my Crawford plenum . And the only way I found it was by preasurizing the whole system . Intercooler ,pipes , motor . When my shop put my motor back together they only put on , one of the 2 gaskets I had on it before .