i was drivin over to nissan n my engine just started to shake alot n u can feel it back fire, i changed o2 sensor and spark plugs, i had p031 n p0037 code. but the noise sounds like it coming from the back of the engine near the tranny, any body has an idea wat it could be, hit me up fast if u knw 7875648984 thank u. i wanna go cruise tomorrow

 

can it be bad gas? i did put gas on base. anybody out there that might knw?

 

i've been using gas on base premium i doubt its bad gas but i have no idea what it could be though

 

lol nevermind thanks to SONIC, had a bad coilpack, anyways replaced them...