Toyota Repair: Engine miss..., spark plug wires, gas filter

Question
I have a 1997 Toyota tacoma with a 4 cyl. (2.8/9 I think)I have just replaced the spark plug wires and the spark plugs because I felt a miss when going down the road. The miss would not be there all the time, it would act like it was starving for gas, and if I let off the gas and gased it again it would stop. It seems to be not when I am gassing it but just barely pushing the gas to keep speed going. This problem got worse it seems when I replaced the plus/wires. I do not have a distributor, so I am a bit baffled. Could it be the gas filter or Fuel injectors(I put in cleaner at least once a month), there is no timing adjustment is there. I do all the work to my vehicles and need a little assistance with this one. I can still drive it but it is annoying, as it will do it more it seems between 45-55. Help.....Allen  

Answer
the first step is to isolate the miss. you need a scan tool for that... look for pendind codes such as p 0300-0304 the # represent the cylinder and 0300 is a random misfire. it sounds like it might be the ignitor pack. but the only way to know is kill one cylinder at a time by removing each plug as you go.untill you can feel or hear the differance. the other possibilty is you may have a bad injector. let me know how u make out. paul