HELP!! I am new to the forum here, so please bear with me. I am travelling from Maryland to San Antonio and made it to Biloxi, Mississppi tonight. My '92 S10 4x4 blazer (4.3 V6 "z" code TBI auto trans) started acting funny just outside of Atlanta this morning. I began to notice a "lurching" feeling--almost like I had gotten a bad tank of gas or something. So I dumped in some fuel treatment, no improvement. I also began to notice that when I accelerate hard I spew a little puff of black smoke out the tailpipe (not blue, very black). Fuel mileage is down from 17 to 7. Symptoms are not constant, they come and go. It will run fine for a few minutes, then run like crap for awhile. Oil level looks fine. Coolant looks fine. It has got to be unburned fuel that I am spewing out. I don't know how the choke system is designed, but I suspect that for some reason the choke is stuck on. Can someone tell me how I would go about looking for loose connections, etc. that may be involved with this system?