What is the proper way to vent a toilet. I have a two story house and the upstairs toilet was fine for ten years without a vent, but eventually it didn't flush properly. A vent pipe was installed, hoping to aid in flushing, but the problem was as simple as cleaning the little hole in the bottom of the toilet that creates the initial swirl. The toilet flushes fine now but I have a continuous gasey odor. I live in a rural area and did my own plumbing, which is now coming back to haunt me. The toilet vent is also connected to my tub drain in the same bathroom. Having said all that, here is the queston. Is there a simple diagram or explanation showing the proper ventilation of a toilet? If my toilet worked well for years (then had mineral deposits) do I even need a vent now?

"here is the queston. Is there a simple diagram or explanation showing the proper ventilation of a toliet? If my toliet worked well for years (then had mineral deposits) do i even need a vent now?"

You didn't need a vent then and you don't need a vent now.
As a rule we wet vent our toilets through the lavatory vent. While toilets can have their own dedicated vent in most cases it's not necessary. If you've had a odor ever since you installed the vent I would cap it off. The tub should also be wet vented by the lav so I don't foresee any problem. Regards, tom