I have been trying to fix a miss at idle on my Blazer so I can get it through emissions inspected. I bought it knowing that it had a gas leak and some other issues. It had an intake coolant leak so I replaced the intake, gaskets, distributor gear and spider injection while I had it apart. I replaced the cat and all three O2 sensors. I also replaced the cap and rotor with accel pieces. The plugs and wires were replaced right before I bought it. I replaced the fuel pump, fuel lines and fuel filter. I replaced the MAF with one from NAPA. The cam retard is at 0 and steady. This thing runs good with no miss fires above idle. I have checked for vacuum leaks at the sealing surfaces and replace all of the vacuum hoses. I looked at idle desired air flow and it is 40 with the tune wanting 39. I scanned the LTFT to MAF and it is only off a couple percent. Hopefully some one has an idea because I'm about out of them.
Ken