I have a 05 dodge magnum sxt with the 3.5 in it . It cranks but wont start i replaced the fuel pump i turn the car on wit the fuel pump line disconnected and fuel is pumping out the top but when i hook it back up the fuel line im not gettin fuel to the fuel rail i disconnected that line to check amd there is no fuel up to the rail so im wondering if the psi regulator is bad

SOURCE: fuel pressure problem.I replaced the fuel pump on 2001 chevy s-10

Most fuel injected vehicles have a relay that controls the fuel pump so after the ignition switch has been on for about 5 seconds and the engine is not running, the fuel pump automatically shuts off.
I don't know what your original problem was, but I think if the car runs normally, you have probably fixed your problem. If you don't have a manual, you can probably go to the library and take a look at a manual that covers your vehicle.

SOURCE: 1997 dodge intrepid

check coil pack/module connector as well.

SOURCE: 2000 gmc jimmy wont start fuel pump comes on and cuts off...

When you hook the pressure test guage to shrader valve on fuel rail what it reads is what the pressure is from pump, around 60 p.s.i. all you need to do is hook up the guage and turn on key, you do not have to turn engine over, and if pump is good it will shoot up to 58 or 60 right now.

mike loshbough

• 1011 Answers
• Posted on Mar 22, 2009

SOURCE: 2000 gmc jimmy wont start fuel pump comes on and cuts off...

the fuel pressure if leaking could cause this the regulator is located under the intake plenum but you should smell gas .if you dont then most likely the pump is bad ,the pump will come on for 2 seconds when the key is on then go off it will not stay on with just the key on only when you crank it will it .so have your fuel pressure checked with a gauge.

SOURCE: 2000 blazer 4.3 hard to start (fuel problem)

Do you have the fuel tester hooked the in the overgrown air valve on the fuel rail in the back of the engine? Or do you have the fuel line unhooked in the back and hooked to the pressure pump? You want the fuel pressure to be in that 60 lb range so if you are hooked into the pressure valve on the fuel rail allowing fuel to go through, then I am betting it is the fuel pressure regulator. To get to that, you have to take the throttle body off and take the plastic plenum that covers the injector packs. On the back of the mount where your six pack of injectors are sits the pressure regulator. If it is faulty then it is dumping fuel instead of holding the pressure like it should.
Get a Chilton or Clymer manual and it shows you in pretty good detail how to fix it. I've done it to my 98 S10 with the same engine.

If you unhooked the fuel line so you are losing pressure from the line back to the pump then I would say your pump is letting fuel back to the tank when it shuts off. My money is on the first possibility though.

Good luck