:confused: I have got an issue with a toilet that is draining slow. It seems to have started after I capped a cleanout access upline to the toilet. Is this possilbe?
I haven't tried to uncap the access, but there is a vent between the cap and the toilet drain.
It is a new toilet, and before I put the toilet in, I ran a water from a hose down the drain of the toilet, and it seemed just fine, did not back up once.
Please help me.

"I have got an issue with a toilet that is draining slow. It seems to have started after I capped a cleanout access upline to the toilet. Is this possilbe?"

Yes it is if the toilet's venting out of the cleanout. I question if the new vent's doing its job. Have you checked it? Open up the cleanout and flush thr toilet. If you have a normal flush then the problem's in the venting.
Good luck, tom