When we flush the toilet it flushing normally but sucks the water back down. It would then just fill back up normally, but now the water just stays down so it is just covering the bottom of the toilet, maybe an inch of water. If I run water in my sink that is in that bathroom then the water in the toilet gurgles. We have run snake in both pipes, the sink and shower that are in that bathroom and this does not help. The toilet was double flushing occasionally before this.

You say "we have run snake in both pipes" do you mean you have snaked your vent pipe? Good luck

It sounds like you have a blocked vent or poor venting, you have to snake it from the roof vent and add 20' more, good luck.

John

Yes, we snaked the vent pipe on both the sink and the shower which are the only two vents for that bathroom

bfulham, I was leaning John's way, but you say the vents are clear? Your sure you went far enough? Sure sounds like a vent problem. Good luck

Vent problem,toilet drain line to far in distance from vent connection,back fall on drian line,or bad toilet because under new international code toilets are self siphoning fixtures.

Welcome AL. We need all the help we can get here but please take note of the date of original post. Don't be quite so cryptic, remember you are talking to home owners not plumbers.