S10 blazer hard starting woes
 

Hello yall
I have a 1999 s10 blazer with some starting issues,one day it will start and run and the next day it wont . When it wont run it fires up and dies in a split second if you re prime the fuel pump it will fire up and then die but it will run on spray all the time. I did a fuel pressure test and got 60lbs at the rail so its not the pump, I'm not sure if this has to do with the fuel injection spider or the fpr or even the crank sensor any help would be good help.
Thanks for your time,
Mike

crank sensor possible, but id lean towards anti theft. got a remote start or aftermarket alarm? whats the security light doing when it disables itself? either way you will need a scan tool to get passlock enable status and cranking rpm. let us know and well go from there.

no aftermarket alarm or carstarter and while its running the security light is out im going to tear it apart this weekend and replace the fuel injector spider and fpr

Well I replaced the spider along with the intake gaskets Ive been driving it for 2 weeks with no problems until last night and it didnt want to start so i let it set for 20min then it started right up. I did notice the gas gauge going wacky a few times while driving it im not sure if that is a sign of a failing fuel pump.My only other thought would be the passlock alarm is failing,is there anyway to bypass it with a resistor like the old GM security systems?

If your gauge is flaking out, there's a possibility that your chassis ground point on the crossmember over rear differential is loose or corroded. It's hard to see so at the same time you remove and clean it, you might relocate it.
On reinstall, coat the clean shinied terminals with grease to keep them from corroding again..

Well I figured it out, it's the passlock thats not making it start, tried starting yesterday morning and it would only crank over and I noticed the security light flashing so I shut the key off and turned it back on and let it flash until the light went solid, it took 7-8 min so then I shut the ignition off and turned it back on and she started right up. So it looks like i'm in the market for a new ignition switch.

did all the other lights on the guage cluster come on when you turn the key?.. I had a situation where my 98 jimmy could not start and my cluster guages did not come except for the security, speedometer and battery lights. Problem turned out to be the ignition switch.