Ok, I got my fuel pressure gauge installed today after work and I did a couple of tests. At idle, I am looking at about 55-60. Moderate acceleration will drop that to 48-50. Heavy acceleration (no load) and I can drop that pressure to 39-40. I do not have a loaded trailer at the moment to test with further burden. Air, oil and fuel filters are all good or new. I have not exaimined the regulator screen. Is this under a cap on the regulator body?
I assume that means in park? I just recently tested mine with a liquid filled gauge. I have a 95 psd with 116k miles. after shimming the fpr I am right at 65 psi at idle and the needle wiggles a little now run it up to 2k rpm and I have 70 psi pegged solid on the gauge, no wiggling of the needle, still in park. don't know if this helps. I believe there is a mechanical and electric pump on yours like mine. if this is the issue it could be one or the other. maybe someone with more experience can chime in with how to test both. also pull your back pressure sensor and make sure it's clean and the tube is open. don't know if that would have the above effect but can't make them run poorly.
I can tell you this though changing out the down pipe to 3" and 4" pipe back with no cat no muffler dropped my egt's from 340* to 230* at idle at operating temps! I then installed an efe stage II cold air intake, didn't see a drop in egt's at idle but did lower it at 65 mph 50*. if you look at programmers you want to at all costs stay away from the edge programmers for your truck!!!! they DON'T WORK WELL with these years of fords, the gauges are not accurate, it shuts off while your driving requiring you restart the truck and it can or will short your computer. either than that there great
yes I speak from experience and was lucky enough after a year of calling them to get them to refund my money. a good controller is the only way to go with separate gauges. I purchased a dp tuner f5 for mine but haven't got it yet. I just installed the 3 in 1 glow shift gauge and like it so far.
