check your oil level first. the check engine light is a failure in some system for fuel control.
you need a shop to diag the check engine light and they must also do a manual pressure test to make sure the engine has enough oil pressure to run.
2 separate problems that need attention.
...s trailing the cAr and it could be coming from muffler thats y muffler is Blackened, maybe...? Oil leak is so bad, its to the point im which a 5 quart oil is gone and doesnt even gets me thru 2 da...