i put new oil switch in and still the oil light comes on when i slow down now what could it be?
It could be low oil pressure. Have a mechanic test the pressure with a gauge. That’s the only way to know the true pressure.
Make model year and miles are all good information when trying to figure a problem out.
While I believe you will find the answer by following mcparadise’s recommendation, I will suggest that you double check the current oil level.