Car problems, chevy blazer, rich mixture

1998 Chevy Blazer 153,000 miles on it. Started bogging down when accelerating. Engine light came on then went off. Showing code PO102 MAF or Vaf. I have changed Cap,rotor,ignition coil. Took out plugs (burnt to a crisp). Checked cat/conv seems ok. Fuel filter is clear of debris. Fuel is 62 lbs when engine was running ( it does not stay running now just dies out quickly). Fuel pressure is 56 lbs when key is on engine off. Placed new plugs in tried to start m/v and would not stay running. pulled 1 plug out wreaked of fuel and black. Do you think I need to replace the Fuel injector spider assembly at $300. or try less expensive parts first? Please help

Answer
    Those fuel injection units are very much prone to failure, and yours is 11 years old as well as having 153K miles on it.  The excess fuel on the plugs is the giveaway.  The richest mixture the computer could possibly meter out would be the starting mixture, which should let the engine start and run.  It starts on the rich mixture from the leaky spider, but won't run on it because the plugs foul rather quickly and stay fouled because the spider is continuing to leak.  I'd be tempted to get a confirmation from a pro, if I was you, but I'd be willing to bet that you have correctly identified the problem.
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