hey guys need some help on this ....just today i went to start my car (has not been started in 3 weeks ) and it would crank and crank and not start ...sprayed alittle starting fluid and she started right up and runs perfect..checked my fuel pressure gauge and it shows 39psi when running (i have a auto meter electiric fuel pressure meter ) ...i have 2 pumps 1 stock orginal intank and 1 inline that came with my procharger ..when i disconnect the fuse for the inline pump and turn the key to the run position (not starting the car ) it shoots up to 43psi and falls to 20psi in about 3 minutes ...ok now when i put the fuse back in to the inline pump (now priming both pumps) it shoots up and right down to 20 psi immediately ...i did check the injectors all reading 14.6 ohms (accel 24 lb) and cheked if the regulator was leaking ,no gas comming out of tube .....

 

honestly it sounds like your pump is dying...if not dead. It would make sense your factory pump dying specially after all this time and with that procharger. Is the external pump a full pump or just a booster pump to "assist" the factory? If its a full pump (and not booster) and its still not maintaining pressure, then it could be a bad pump or its having trouble getting fuel from the tank. Be it trying to suck fuel through the intank pump or the rubber hose that connects the intank pump the the hard line inside the tank.

A final thing it can be is bad voltage or bad relay...

 

yeah not sure if its a booster or a full pump ....

 

honestly, I would say its a booster simply because it can't keep up the fuel pressure on its own and forced induction systems normally include some sort of fuel management system, be it mechanical or computer... The problem is between your fuel rail and your fuel tank. The injectors don't affect fuel pressure (atleast not like this). Have you changed out your fuel filter? There is a slight chance it can cause this. Its only about $10 to replace...

 

If the filter doesn't work, you need a fuel pump...

 

im pretty sure its not the fuel filter (changed that about 9 months ago) plus a fuel filter wouldnt cause fuel pressure to drop like that ... why do you guys think that with just the intank pump priming it goes from 43psi to 20psi in 3 minutes and when i have both intank and inline pumps priming it goes up right away to 20 psi imediately (just the key in the on position)

 

Not enough voltage? Are you supplying both pumps w/ the same elecrical feed? If so that could be the problem???