I've noticed that my engine stumbles much more than normal when the A/C compressor kicks in. This is especially noticeable when sitting at a light and the compressor kicks in. I know the engine always adjusts when the A/C kicks in, but the stumble/drop in power/RPM is much more pronounced. What would be the possible reasons for this? O2 sensors aren't very old. Back O2 is a couple years old. Front is a year old. 96 C280