alero 2.4L ruff idle

[blackbeast]

i have a 2001 alero 2.4L has about 58000 on it

i have noticed that is seems to run louder than it normally does about 3 weeks ago and seems to idle ruff .
i got the plugs replaced and put new boots on and got the transmission flushed so i'm thinking maybe an o2 sensor.
the other thing i noticed is about 1 months ago the noise for the air pressure/and the oil pressure doesnt seem to make any noise .so i dont know if that is a good thing or bad thing.
any help on the ruff idle.........

[Gr1m]

IAT sensor, MAF, o2 sensor, bad gas.. could be a bunch of things
atleast on the 3400 dont know about 2.4

[Oldsman]

is the service engine soon light on?
if O2 was going bad it definitely would be.

it could be a vacuum leak or maybe igintion module. so many things

[blackbeast]

no there are no lights on just me knowing the change