I have a 2001 blazer xtreme. The ignition cylinder was broken, I got it replaced today, by the way, the truck was sitting for 2 weeks. So the battery is completely dead, I got a new one in and the truck just kept turning and turning untill the battery was delpeated. I had a fuel pressure test done a month ago and i think I need a new filter, its running at around 45psi at idle, and when you apply the throttle it drops. My question is that is there something I need to do to get it running again after I change the ignition cylinder??

 

Put a pressure guage on it - let the pump prime - check the pressure - if it is below 52psi then it won't even think about starting...

Then you have to determine if it is a clogged filter or the fuel pressure regulator has failed...there is also a pressure related part in the top of the fuel tank...

Good luck!!!

my first hunch would be pressure regulator then filter..

 

Well I got it running, the mechanic was trying to fix it for he longest, finally he called a dealer and apparently when something like that changes a security thing happens where it shuts off certain things with the truck. So, they gave him certain steps to take to manually reset the code to the new key and ignition cylinder. Steps like opening and shutting the door so many times and wierd stuff like that. Otherwise thanks for the posts and hopefully this helps someone in the future!