Ok well I noticed my car is bogging down to like 2900rpms when I shift into 2nd gear I know I have a bad o2 sensor drivers side downstream. Also I have no cats so the cel is on. It feel like my car loses a lot of power when I floor it from the start. I Don't know if it ever did this before cuz I don't drive it much and never beat on it. A little history about the car 57k miles flowmaster 40s, mac pro chamber h pipe....any ideas or tests I can do from my house??