Yes CO at idle controlled by lambda, UNLESS it is faulty!!
When they go duff, they can still have a good within scale lambda reading but the switching speed drops off, the result is usually going way off scale mixture wise.
The tps is just tested by seeing how it reads as you slowly open the throttle, that is about all you can do, sometimes you find it has a dead spot around idle or near there, is the common place but could be at any point.
tabetha