Is the check engine light on? If so, have the computer scanned for codes. There are some auto parts stores which will do this for free. Once you have the codes [if any are present], post them here for further assistance.
The engine oil has nothing to do with the black smoke. However, it is a good thing you changed it; now you can begin tracking you maintenance.
Wednesday, June 19th, 2013 AT 7:16 PM