hard starting on 2000 GMC Sonoma

I have a 2000 gmc Sonoma 2.2 most of the time after the engine is warmed up its hard to start? also I have an oil leak running on top off my exhaust where and burning.its located on the exhaust pipe between the motor and transmission.i have an a/t. any advise would be nice.just got this trk and don't know it.

Asked by for the 2000 GMC Sonoma