Okay so I did an engine swap in a 1991 s10 blazer LT Tahoe edition. The guy I bought it from said it struggled to run. Before the swap it had the same condition, hard start and black soot from exhaust. I replaced the egr valve and tps and it ran better so I decided to proceed with the swap. After swap I got it running and had same condition. At idle if goosed it would just sputter and die and struggle to start again, found that there was a wire underneath the passenger side to set mechanical timing. I also did research and found I could have a bad iac so I replaced the iac and unplugged the wire to set mechanical timing and now it wont start at all. It's also 30°f here right now. Running to the end of ideas here. Any one know anything els that might help?