2.5 engine cold start up rough running for about 1minute then runs fine, why? on 1991 Jeep Wrangler

this started after someone try to tune it up and it has drop gas mileage

1 answer 1 comment
sounds like fuel issue.poss vac leak or floodling condition cold.
I'll check vac. line again. Did have fuel pump replace not to long ago but this was happening before that.
Recheck vac. line found one crack in tee. still rough at cold start-up, I am talking temp at 40 or lower.