I want to take out the fuel injectors on a 98 cavalier 2.4l and replace the O-rings and clean the injectors themselves. Anyone that can help me with a step by step guide?

Also, the reason I am doing this is because my mother (it is her car) is smelling gas and the care SOMETIMES run rough. Mostly when there is a heavy load on it (going up hills, etc..) Any suggestions as to what that could be or am I starting in the right spot? She is very poor and can't afford a shop to look at it and I'm fairly handy with a wrench, but I have never dealt with injectors.

Please advise. She is coming tomorrow to have me look at here car.

Thanks in advance for any help you can give, I appreciate it...

Anyone have any suggestions?