My car does not have any power going uphill. I drives ok going straight but there is clearly a lack of power.
Symptoms:

RPM will not go above 4500 even when going straight.
In Neutral the motor will not go above 5300rpm and when letting off the gas the motor will die or just barely run for 10-20s untill it reaches idle.

Codes I pulled P1149 and P1399

I cleaned the TP sensor and the O2 sensor plugs with contact cleaner.
I unplugged the spark plug wires one by one and it seems like the engine is running on all cylinders.

What should I do next?

 

Replace the primary oxygen sensor in the exhaust

 

Ok did it, changed the primary oxygen sensor Honda OEM part with matching numbers.
car is still gutless. It feels like it hits the rev. Limiter when driving not rpm over 3000 possible. I was not able to go above 40mph

Codes say engine is running lean P0170 and P0173.

 

What year and model are you driving?

 

2000 accord ex coupe with the ulev vetec 2.3 4 cyl motor.

 

How do the plugs look? Verify gap is correct.