1999 Toyota Camry sluggish and makes popping sound on accel

Just the other day out of the blue about halfway thgru my drive home the car suddenly had difficulty in accelerating. In stop and go traffic, when stepping on gas the engine would seem to choke, then an air popping sound would be heard in engine compartment (sounded like it was on drivers side near firewall) but woud eventually get back to normal. Problem is really noticable when going 'uphill' from a stop or uphill when needing to accleerate even more .... slugish as if it wanted to stall, then choking type air popping sound, then off it would go.

Have left car in driveway until this weekend to look at, could this be a vacum hose type of issue? Any input woudl be helpful