2001 V70 XC AWD 2.4 Turbo -- Power Loss

[snazycon]

I have a 2001 Volvo v70 2.4L turbo AWD 5 cylinder.

The car seems to want to top out around 15 to 20 mph randomly. The car initially threw error codes for bad o2 sensors (P0031 P0030 P0037). I replaced the sensors and the codes went way but the power issue remained. The catalytic converter does not get red hot after driving for a while. I am wondering if anyone might a have an idea what it might be.

Other Details:
I had the cylinder heads replaced.
The car seems to also lose power when turning.
The Shifting does not see to shift hard.
The seal in flange between the catalytic converter and the resonator is rotted out.
Power-steering reservoir leaking.