when i turn my car on it smells sort of a slight gassy (coming from the Defrosters/ AC vents) but once i get on the freeway it smells a lot more. when i bought the car off the prior owner it didnt have an O2 sensor because it a d15b japanese engine block. can anyone help me with this?
and also light it burns oil faster than a usual 91 civic

 

What kind of car? Model/Year/Trim/Transmission ?
Is there a hole in the exhaust piping because there are no o2 sensors?

 

its a 91 Ef i believe its a 91 transmission i'm not quiet sure is there a specific way I can check that??