I've had my 03 coupe 6mt for about 3 years now, and the only problem I ever had were some bad 0 2 sensors, I would change the air filters, oil and filter etc, even the spark plugs.
About a year ago my car started to run real poor, it idled high, it would stall, and consume so much gas.
I've tried everything, I've changed the spark plugs, I'd clean the maf sensor, throttle position sensor and it would not fix the issue, but it would get alil better when I clean the intake system. I believe this issue started after I changed the o 2 sensors a year ago, could it be?? In cold starts, it would surge almost like there is too much gas in the motor on start up, so the car would choke up alittle and it has a random misfire too... Last codes I got was, idle was too high, and another one that said, running rich I believe, I've tried it all, have you had this problem? I've done the relearn process, all of them and nothing seems to work. Help please!!

 

I've noticed that when I shift, and give it gas, the air suction isn't as loud as it used to be, now it's very feint and low slow and boring:/. It used to be so much fun but boring now, please help

 

maybe you need a tune! or an air sensor if its bad gas milage