My 924 porsche has idling issues. It starts then putters and dies. If I keep messing with the accelerator, its fine. I put by fingers in the air intake (I think) and there is 2 what feels like screws, I touch them, that is all touch them and the car purs like a kitten. I have been looking for an adjustment screw to maybe pull it a little tighter, but nothing. Something appears to be missing, but I dont know what, I am new to cars, have no chilton, just can fix things, usually, hope I explained that enough, Please help