hey, i have a 2000 civic sir which is an usdm si. it has the stock b16a2. today when i was driving the car seemed to lack power. if i had my foot on the pedal it wouldn't seem to be the same, then it would start to kick in like it was normal again without moving my foot. anyway i made it home and checked the oil, it wasn't too low but it was full a few days before. So i filled up the oil, let the engine cool down and then tried it again. this time smoke was coming from the exhaust like a old man smoking a pipe. the car didn't cut out but it had no where near the same amount of power and it had a loud knocking sound every 10-15 seconds or so. pleaseeeeeeeeeee can someone give me an idea of what this is. the car was not bone dry of oil too btw. only bought a month ago

 

possibly a blown head gasket?

 

also about a week ago i had a sound like something was loose when i would idle a bit. it was something with the exhaust. i took it to a guy that does my work and on the way there it went away lol. he said it didn't sound like it was serious, which i figured. he said drive it anyway. now this ... and yeah i was thinking it could be the head gasket but im no mechanic so i figured i would make a post. hopefully its nothing serious