sputtering and stalling out

when  i crank it up its fine until a mile or so down the rd like once it has warmed up a
lil, it starts sputtering for a second or two. When i come to a complete stop and start to
go again it acts like it wants to die out. It didn't do any of this until after i changed the
above things - the semi tune up - Checked for vaccume leaks but didn't seem to find
any. A friend told me to spray some carborator cleaner or something like that on it just
in case there's a leak down in the there that we aren't noticing.  Do you think that all
this has something to do with spark plug wires crossed or maybe dirt being on the
plugs when they were put on cuz it ran fine until a buddy did this semi tune up for me.  
Please help cuz i don't wanna mess my car up by driving it under these conditions.