|WYG|SS

ive posted about my truck missing. and now im thinking it is the FPR how do you test this. the guy at advance told me to disconnect the vaccume hose and if it changes( and i forgot what that meant if it chages). now i disconected it on the FRP and it doesnt seem to chage and when i disconnect it on the other end of the vaccume line it changes. do i warm up engine first? i have no pressure tester.




edit: went to harbor freight had a sale on one for 9.99 so got it and did a test. engine not running was at about 10psi which haynes manual says it should be between 45-60 psi. then engine running says 20-30psi and it was at 45psi bouncing around alot. i think i got a sticking fuel injector. is the needle not supose to move? and the needle filled up with gas is that good?

Kattumaram

Equipment: 0-60psi guage, hose and Schrader valve adapter.
Hand vacuum pump with suitable hose.

Connect pressure guage hose adapter to the Schrader valve port on the fuel rail.

Key On Engine Off: fuel pressure 30-45psi
Key On Engine Running: fuel pressure 27-42psi

Leak down test: KOEO: Note pressure. Turn off key. Noted pressure should lose less than 5psi at one minute from key off.

Test the fuel pressure regulator diaphram with a suitable vacuum pump with an attached vacuum meter. Pull a vacuum of about 20 inches at the vacuum port on the regulator and hold....the reading should not change.

And yes, some fuel will leak out of the system and tool attachments as you go about testing the rig.

FYI: The KOER fuel pressure in my '97 4.6L is 32psi.