89 Mazda smok'n bad'ly

I have a 89 Mazda 626,runs great except that I have a small oil leak.I put some Engine Oil Stop Leak (BIG MISTAKE,WILL NEVER DO THIS AGAIN) in it and now all I get is white smoke and it cuts off when I take my foot off the accelerator.Any suggestions will be appreciated.I'm thinking that I could have clogged up my Cataytic Converter by using that oil stop leak.I did flushed out the old oil, use engine clean gunk and put new oil and filter in it.What do you think?.....i miss driving my 626 5 speed stick. Thanks

Got it running again.
All I did was just flushed out the fuel line and put 2 bottles of concentrated STP gas treatment and that done the trick.Thanks anyway for all your help.I think that there was water in my tank (maybe,don't know)