I just replaced the 2 fuel lines and have installed a fuel pressure gauge into the line that runs to the fuel filter... The gauge is for an efi car but is a mech gauge and reads up to 100psi.. When i done it my car was warm but not too cold or too hot... Everything installed cracked the car over and watched the gauge its sitting on 36psi at idle does that seem right? What are the pressures for when its on cold start up so i can see if the pressure is correct... Also when the car is off should the gauge show how much fuel pressure is in the line still or no as its reading 0... I can hear the fuel pump prim before i crank it over then when i turn the car off i hear the same sound like its depressuring the system...
See Ash's the 6 P's post here I.E. 36psi at idle is fine. You always want at least 43.5 psi pressure difference. So if you are running 10psi boost, you want at least 53.5 psi on your fuel gauge. See article for more info. :zlove:
Cool thanks for that was looking but could not really find what i was after... Since going for a drive the gauge is reading 35 36 psi with the motor running at idle and with the motor turned off so thats a good thing then.. Just got to let it go cold over night and start it up and see what the reading is on cold start up... I am only running stock boost with an MBC for now till i deside if i wish to turn the boost up hehe
Beat me to it! Also most quality aftermarket fuel regs have an outlet for a gauge, might be worth looking at if you are planning to upgrade your fuel system down the track?
which line is that one beaver? rob260: yeah most likely down the track i may upgrade my fuel reg as well as my injectors but right now the stock system is fine... I know a lot of aftermarket fuel regs do have outlets for a gauge... The gauge reading its pretty good so when it is on the dyno will know what the pressure is when boosting... I just wanted to make sure that the pressuring it is reading is correct... So does anyone know what it should be at on cold start up? I am guessing it should be more due to the car pumping in more fuel on cold start till the car is warmed up...
The return line from the passenger side of the fuel rail, before the FPR. Mine is set at 38.5 psi for the tuning that I have, although my setup isn't stock, Sard 650 injectors, Bosch fuel pump and Sard FPR.
Well its a prick to get at for starters.The line comes off the out side off the fuel rail, and then connects to the stock fpr. If you poke your head over the regulator and look down at it, you should see a fuel line that disappears under the plenum off the front of the regulator, that?s the line your gage should be in.
Nath, 36 at idle is fine. In regards to the pressure, when I switch my car off, it holds fuel pressure for about an hour. ie, it takes just over an hour for the gauge to read zero. Cheers
Yep its doing that now Mark since i took the car for a drive let it sit and checked an hour later and it was almost at 0 so thats all good hehe at lest its fine at 36 psi... Do you know what the min psi level is?
