2.4L Cavy Rough Runnin

2.4L '01 chevy cavalier runs super rough. I did a full tune-up including new fuel filter, new air filter, new plugs, new plug coils, oil and filter change. Someone suggested that it could be the vacuum lines. Braking is still good. How do I check the vacuum lines?? :confused:

If it's a vacuum line you will hear a hissing noise under the hood, Do you hear anything like that?

Have you checked all the pulley's to see if they are all spining correctly?

Also, what exactly is it doing, You say it's running rough but that could mean alot of thing's.

When you hit the gas is the power instant? If not it most likely a vacuum leak

Delayed power, yes. I will listen for the hissing and check the lines for damage THANKS Josh :)

Sure all the intake hose's are secure? I've had this problem with my car and the intake hose had sliped off on the one side.

Have you replaced the Oxygen Sensor? You'll need to replace that at least once a year.

I think it musst be the O2 sensor. Anyone know how much a new one will run?

Oh, Jez.... $20 give or take. It's about time for mine too

Is the check engine light on? If it is, have the car scanned and you should get a code which will help you determine the problem. If the O2 is the problem, a code should come up. I figure the car was running rough before and this is why you gave it a tune up? If it wasn't running rough, double check the wire routing. I have also run into a bad plug a few times( even though the plug was new.)

mine is running rough to. I was told to clean the IAC