2001 Chevrolet Blazer

Engine Performance problem
2001 Chevy Blazer 6 cyl Two Wheel Drive Automatic 147000 miles

2001 Blazer 4.3 v6 147000. Intermittent cold start problem. My truck is hard to start maybe twice a month in the mornings. It is especially hard to start after rainy, humid weather. It turns over, then immediately sputters and dies out. If I press the accelerator during starting, it will sometimes eventually start, after softly backfiring in a few attempts. Yes, I do smell gas, but no black smoke is apparent. I have had the plugs, wires and cap changed. I have replace the fuel pump, filter and spider-piece (injectors). After it starts, there are no more problems for the rest of the day. It runs great. Gas Mileage sucks though. It used to emit a raw smell which my mechanic suspected to be coming from the catalytic converter. No other symptoms though. What gives!
September 21, 2009.

Check and make sure the crank sensor is clean and tight. Also, has the check engine light come on?

Thank you for replying : )

I will check the crank shaft sensor. The check engine light has not come on. It has also started to bog down under heavy acceleration, but it doesn't do it every time.

Oct 20, 2009.
Let me know what you find. Also, check for vacuum leaks and make sure the EGR is working properly.