I have an '87 k5 350 TBI and have had a stumble/stall problem for awhile now, the thing will run fine and then decide to stumble and wont rev, then it would suddenly jump up to idle after slamming the gas pedal a few times and then run fine and then do the whole thing over again, sometimes just stalling out completely. I first thought it was the fuel filter, so I changed it and she ran fine....a few days later did the same thing. So I finally said fu$* it and put a new gas tank, sending unit(needed one anyway), fuel pump, and filter on and she ran fine for about 350 miles and now is doing the same thing again. I cant seem to figure it out...any suggestions??? Could it be my injectors? I still have my stock fully rusted out exhaust.....could that be the prob....maybe clogged cat????? HELP!