when I pull oil filler cap off theres milky residue on the cap and around the rim it doesn't go down in the pan just residue at top
That's emulsion. A mix or water and oil (yes, they do actually mix) and usually a result of many short trips, like a few block and shut off, then home again. Running the car on the highway for 20-30 miles at least once a week will eliminate this, as long as your dipstick has clean oil. If you do a lot of highway driving, and still have that emulsion you might have another problem. It looks like this? Or like that but not as bad? click image
Could also be the result of a clogged PCV (Positive Crankcase Ventilation) system. Check the PCV valve and hoses. Make sure they're not clogged, damaged or misrouted. HTH. -Jim
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