Working on two camrys

[Lee250]

I'm working on both my own camry and my brothers. Both are 86s with auto trannys. His has 186000 mile and blows a bit of smoke. He said it has also lack off power. I did a compression check and all 4 cylinders are between 150-165psi. I checked for codes and I got number 5 which is oxygen sensor. Will just an o2 sensor cause a big power loss? My camry has 224,000 miles and has way more power than his but I also have an o2 code as well as code number 6. What is code number 6 mean? The repair manual says rpm signal, no NE signal to ecu while cranking or NE value over 1,000 rpm in spite of no NE signal to ECU. What part excatly needs to be changed? Also both cars have had EGRs plugged and both have new timing belts and don't have any misses. I have no complaints of power on my camry but was wondering if fixing the sensors would improve performance or MPGs.

[Sturdavj]

When you say “blows a bit of smoke”.

1. Is this upon initial start up?
2. When leaving the intersection after waiting for a traffic light?
3. While traveling down the road your leaving a smoke trail behind you
4. All of the above

How much oil is the car using} ? Miles = 1 Quart of oil

[Lee250]

I would say 4. Idk how much oil it's losing. I have to ask my brother.