@Nick13066point0 the main issue here is the unexplained dip and generally erratic readings.. i can live with the gauge being constantly off by 10PSI, but not fluctuating like it does :S
@rmelton28 i don't have a mechanical gauge on the rail, i'm comparing the reading from the OE fuel rail pressure sensor and the Autometer Nexus Fuel pressure gauge..
the OE sensor never reads such a dip.. pressure is rather consistent while idle, rises as i go WOT then drops back to ~39PSI.
as for the autometer sensor, it's installed on the back of the passenger rail: i.imgur.com /x8J5D.jpg (remove space)
This is normal. The fuel pressure regulator adjusts the fuel pressure on the fly based on manifold pressure/vacuum. This is to increase/decrease the fuel pressure so that the same amount of fuel flows out of the injectors, as more fuel flows at the same psi with a vacuum in the manifold, than with say 10psi in the manifold, because the fuel pressure needs to overcome the manifold pressure.
The ratio is 1:1 and this is standard on all direct fuel injected vehicles.
i didn't just catch it on the gauge, the car basically falls on its face if i don't shift fast enough while going WOT, as the fuel pressure drops a bit too low for it to climb back up to normal levels quick enough.
so i'd be back in the higher gear, dump the clutch and floor it.. not enough fuel, and the car stumbles.
ok i see what your saying. well i dont really know about that i did it run fine befor u put it on there? the fuel psi regulator you mite need to put a biger fitting on the regulator.
can I ask you something did you use a fuel pressure adapter to hook up you fuel pressure gauge
ztepcs11 1 month ago
@ztepcs11 i drilled a hole and welded a 90* elbow on the passenger side fuel rail: i.imgur.com /1iraO.jpg
DXBLouie 1 month ago
@Nick13066point0 the main issue here is the unexplained dip and generally erratic readings.. i can live with the gauge being constantly off by 10PSI, but not fluctuating like it does :S
DXBLouie 1 year ago
@Nick13066point0 i replaced both the gauge and sender eventually. and i have the same problem now where idle fuel pressure reads 10psi (too low)
im gonna check the voltage at the sender and see who's the culprit
DXBLouie 1 year ago
@rmelton28 i don't have a mechanical gauge on the rail, i'm comparing the reading from the OE fuel rail pressure sensor and the Autometer Nexus Fuel pressure gauge..
the OE sensor never reads such a dip.. pressure is rather consistent while idle, rises as i go WOT then drops back to ~39PSI.
as for the autometer sensor, it's installed on the back of the passenger rail: i.imgur.com /x8J5D.jpg (remove space)
DXBLouie 1 year ago
Did you ever decide if this was a defective sender, or was working properly? I just got my set installed and is exhibiting the same behavior.
comando292929 1 year ago
Typical bad electronic gauge. Its either a bad sending unit giving false readings or the gauge its self it bad.
It took me 3 tries to get one that worked correctly. Seems quality control has gone out the window at Autometer.
papabugs71 2 years ago
maybe dirty fuel filter or sticking injectors. try some in-tank fuel/injector cleaner. I usually use it every other fill-up.
lackadaysical 2 years ago
holy fuck $300 per gauge?!?!?!? ill stick with the colbalt or C2's
shaun52282 2 years ago
buy a new one?
bbrla123 2 years ago
300 per guage fuck that gets some defis for that
bigguns1997 2 years ago
thats strange, its like an oil pressure guage. higher rpms=higher pressure.
maybe the sending unit on the regulator (or rail) is loose. have you had very poor gas mileage since the install?
turfshredder 2 years ago
sounds like a mustang cobra :D
nextrider123 3 years ago 2
how much did u pay for these guages
Kareem2369 3 years ago
~$300 per gauge.
some were less some were more, but that's the average you should be looking at.
not exactly the cheapest :S
DXBLouie 3 years ago
guages make you faster
jayguy173 3 years ago
This is normal. The fuel pressure regulator adjusts the fuel pressure on the fly based on manifold pressure/vacuum. This is to increase/decrease the fuel pressure so that the same amount of fuel flows out of the injectors, as more fuel flows at the same psi with a vacuum in the manifold, than with say 10psi in the manifold, because the fuel pressure needs to overcome the manifold pressure.
The ratio is 1:1 and this is standard on all direct fuel injected vehicles.
OVRTKEU 4 years ago
oh, actually now I see what you mean where it dips there for a sec. I wonder if your fuel pressure is actually doing that?
OVRTKEU 4 years ago
i can datalog the dip too..
i didn't just catch it on the gauge, the car basically falls on its face if i don't shift fast enough while going WOT, as the fuel pressure drops a bit too low for it to climb back up to normal levels quick enough.
so i'd be back in the higher gear, dump the clutch and floor it.. not enough fuel, and the car stumbles.
DXBLouie 4 years ago
man i reallllllllllly want these gauges
JoESkiLoVe17 4 years ago
ok i see what your saying. well i dont really know about that i did it run fine befor u put it on there? the fuel psi regulator you mite need to put a biger fitting on the regulator.
bigwhiteboy279 4 years ago
i dont see whats wrong. when you give it gas the meter is read more PSI. so i dont know lol..
bigwhiteboy279 4 years ago
Well it's supposed to idle at 39PSI.. but as it turns out ~30PSI at 20 inches of vacuum is just fine.
what i still don't understand is why the pressure dips below the idle level (notice as i let go of the throttle it dips below 20PSI)
now this is only at idle, but this is becoming an issue while driving as the pressure drops down while shifting.
similar to the notorious PPRV related problem on 03-04 Cobras with dual fuel pumps.
DXBLouie 4 years ago
notice how the fuel pressure drops shortly after.. it's not supposed to go below 28PSI :)
DXBLouie 4 years ago