1999 Suzuki Esteem engine cut out

Electrical problem
1999 Suzuki Esteem 4 cyl Front Wheel Drive 130000 miles

My suzuki which has run great for 100,000 miles started cutting out at 55mph when you would try to accelereate to pass. It ran fine as long as you did not push to hard on the gas pedal. This continued to get worse over the months until it was cutting out going up hills and now will not run at all above 35mph. I dont think it is a fuel problem because it only cuts out for a second or two and all four cylinders are dead no sputtering or jerking just dead. I think it might be the coil? Any suggestions would help. The car is not worth much so I dont wand to spend a lot of money trying things that dont work. Thanks.