Fuel Pressure changing is this right.

2000 1 ton
5.7
replaced fuel filter and ran a can of fuel injector cleaner at the fuel rails yesterday


Did a fuel pressure test.

Truck at idle is 50psi
I hit the gas and the pressure goes up to 60 psi.
Turn truck off pressure goes to 60 psi.
Start back up and at idle the pressure is at 50 psi.

Is this correct or do I need to replace the fuel pressure regulator?



Thanks in advance !

Those numbers are about correct. The fuel pressure regulator varies rail pressure based on engine vacuum. When you blip the throttle, vacuum falls off and fuel pressure increases. When you shut the engine off, vacuum falls off and regulated fuel presure again increases (the PCM runs the pump for two seconds after the last ignition reference signal, and the auxiliary oil pressure switch may run it even longer than that).

Those numbers are about correct. The fuel pressure regulator varies rail pressure based on engine vacuum. When you blip the throttle, vacuum falls off and fuel pressure increases. When you shut the engine off, vacuum falls off and regulated fuel presure again increases (the PCM runs the pump for two seconds after the last ignition reference signal, and the auxiliary oil pressure switch may run it even longer than that).


Thanks for the info.

After I replaced my cap and rotor (AUTOZONE cr*p) with ACCEL my engine is running like new. Also replace coil with an accel.

I used to get 183 miles on a half tank, now 183 on a 1/4.

Checked ohms on the old rotor and cap and could not read too much build in **IN 6 months that is was in my truck**

Also notice the cap was never tight....

ONLY TOP PRODUCTS FOR NOW !!!!!


Later !!!