A-dub5513

I'm not exactly sure what the problem may be, but it appears that I'm not able to build fuel pressure.

So far, I've replaced the pump, and just today, the fuel filter. I'm wondering, is it possible, or even likely, for pieces of the teflon tape that [I]was[I] used to attach the under hood fuel gauge and the fuel sender on top of the filter to flow downstream and clog the injectors?

The teflon tape was recommended as per the B&M instuctions for the gauge, if I remember right, but didn't use it this time around.

Thanks for reading,
Adub

GSRRacer95

Anything is possible, but I think it's extremely unlikely. Have you hooked a fuel pressure gauge to the fuel rail to see what the current pressure is?

Lynxs1981

Do you have fuel at the filter? If you have fuel at the filter, then you likely have a leak someplace along the rail, and stuck injector, or a faulty fuel pressure regulator. A clog down the line would usually cause high pressure since it can't be bled off.

A-dub5513

GSRRacer: How/where do I hook a fuel gauge to the rail? Furthermore, doesn't the filter-top fp gauge measure pressure from the filter outlet (after filter element) down to the injector nozzle point? If that's the case, then yes, pressure is true there.

Idle pressure and off the line performance seems ok, but when I open the throttle, it seems like pressure rise rate isn't keeping up. However, if I raise the rise rate on the rugulator, the car bogs (too rich) off the line.

Lynxs: Yeah, fuel's definately gettin' through the filter and there doesn't appear to be any signs of leakage. I felt the same about this scenario being on the unlikely end of possible theories, but as mentioned above, it's weird how I've had all the infinite adjustments down to where a slight adjustment was either too lean or too rich...

...that was with the OLD filter. Just yesterday, I noticed quite a bit of difference with the new one. First, the pump primes half as loud (a good sign of improved flow) and the car no longer hesitates off the line on an incline.

So far, thanks you guys for chiming in. Happy to receive further suggestions. However, since the filter install, things seem to suggest new adjustments to the fuel delivery is required before making further judgement.

Adub

A-dub5513

So here's the update: I just took apart the AEM fuel regulator and everything looks good (clean, no grime). The kit came with three interchangable orifices (.100, .150, and a .200). My intention was to check and confirm which orifice was currently installed and perhaps determine whether that was the possible bottleneck. Anyway, the largest port was already installed.

According to the install literature, the regulator was designed with a range of 20 psi min. to whatever aftermarket pumps can dish out, depending on which port is being used. However, my situation remains where I cannot get a lower static pressure of 36 psi to the desired 32 psi. Don't think it's my FMU, because theoretically, the static pressure was set with vacuum line disconnected from the AEM so therefore set independently from anything down the flow path(?). So the set screw on the AEM is now at its lowest setting (furthest counter-clockwise), right at the point where pressure will just start to build, but not backed up so much as to lose pressure as the diaphragm expands when I hit the gas pedal (losing pressure).

So what gives?

Adub

Spec R

have you tried swapping in the OEM parts, just to completely rule out the AEM parts?

cruzalekz

hook up the pressure gauge, then adjust the fuel presssure regulator to spec. but you need to know the spec for the correct pressure for your engine. from the filter to the tank, you should be good so dont take anyting apart there anymore.

archebald23

sounds like a bad pump to me too. Did you put a Delco in it? Yes you have to know the correct ways on how to replace a fuel filter then present your info to the parts store manager to secure some warranty and you might goose him for some labor consideration.

cruzalekz

he dont know what hes doing