my 1992 sentra e wont pass smog. i did plugs wire roter cap oil and cleaned my k&n filter. was a 216 at idle of hc after tuneup its now a 350 wtf. any ideas? i have an underdrive pulley and header. i cant for the life of me figure it out. the smog dude mentioned misfireing but i cant hear it, only the engine shakes funny a couple times a minute. any help make me happy.