ok thanks i will try that later tonight. if it leaks down you think the regulator is bad? and if not where should i look? idk sux cause this issue is causing it to have horrible fuel mileage.and at the moment its all i got to get to work cause i got my pickup tore apart doing huge performance upgrades.. what a time for the blazer to break...

 

so is it possible a vacume leak around the intake could be causing the regulator to mess up?

 

Without isolating the pump, there's no way to tell if the leak is in the plenum or in the tank. If you remove the plenum, you can apply vacuum to the regulator, it should hold 20" of vacuum indefinitely. If you install the fuel pressure and return lines to the injector pack with the plenum removed, you can energize the pump and check for external fuel leaks. Don't start the engine with the plenum removed.

 

That would only increase fuel pressure, it would not create any fuel leaks, or cause leakdown to change.

 

O. OK gotcha

 

k well i went to take off the intake to do the regulator and see of it was wet.... this was before i saw ur pm.. saw that where the pcv valve connects to the intake was completely off the intake.. so just to see what would happen i plugged iy in all the wires back up and started it back up. it ran a whole lot smoother. fuel psi was about 55 running. shut it off the psi went up tp 59. started takeing stuff off to try to get to the driver side motor mount cause needs a new one.. got dshaft ant exhaust outta the way and still cant seem to get to it... wella any way a lil over an hour went by and psi only dropped 2psi now reads 57. so idk whats goin on?? i wouldnt think fixing that huge vacume leak would fix the fuel pressure?

 

Vacuum leak will have no affect on fuel pressure. Leakdown to 57psi in an hour is not excessive, it's fine. As long as key ON engine OFF, fuel pump running, fuel pressure is 60psi to 66psi, fuel delivery system is fine.

 

that driverside engine mount is a pain... pretty mu h just need to put the ypipe and drive shaft back in than i can drive it and see if it help hope so.. but yea i agree idk how it didnt leakdown just by puttin that thing back on the intake. but yesturday it went from like 60psi to 0 in a hour or a lil more. today its been about six hours and still has 27psi. wich i guess is good? but thanks for your help. there has to be a issue somewhere cause thats all i did

 

I agree, there's a problem somewhere, but without it acting up, you ain't gonna find it. Probably will need to isolate the pump when it's acting up, that will tell you which end of the truck to start looking.

 

ok well guess iam gonna have to pull the plenum hook the lines up and see if i see anything... and just replace the regulator while its apart. drives much better has more power. but when comming to a stop it almost stalls than idles great until igo to take off. it sputtters falls on its face almst dies than clears out and runs great????? idk was thinkin maybe crnk sensor messing with the timming. but engine light came n for the samething agiam bank one lean and bank two lean????