I brought a used 2012 386 Pete with Cumming ISX15 engine last year with under 400,000 miles that came from Indian River Transport. It's in the shop ever other week it seems. The engine light keeps coming on, and I'll replace sensors, replace def filters, egr, you name it it's been done. Always after a couple of days the engine light comes on. Is there a way the reset it. There has always been an air leak that no one has been able to find. It leaks down to 50 lbs, and will stay there for days. Is there an answer?