ok i have a 04 g35 coupe 6mt sport about 73,xxx miles (stock)
I recently put the jwt pop charger and heatsheild but kept the g35 stock tube. I also changed oil 5w30 mobil1 synthetic and nissan oem oil filter the same day. I searched for some info couldnt find anything so heres this thread thanks for helping

1.Car sounds louder at idle? rpms are higher at idle as well? is this normal im sure it is but sounds like i have a aftermarket exhaust?

2.After driving a few miles the service engine soon light pop up on the cluster? has this happened to any one?

3. Very bad mpg i used to get 18/19mpg city now its like 13-15mpgcity

4. Also the car seems more sluggish? at WOT rpms are picking up slow? car was sluggish to begin with thats why i thought it was the dirty oem air filter but i guess it wasnt. Possibly fuel filter?, sparkplugs? ecu reset? i dont know

any input/help/suggestions thanks...

 

i had the same problem just recently but mine was because one of the spark plug connections came off. now is your check engine light blingking if it is stop driving hah if not take it to autozone get a free reading and see what it says if your too damn lazy to do that loLloL make sure your maf air sensor is properly connected and make sure you didnt mess up that lil tube inside the sensor. other than that idk what else could be the problem.