Apparent Fuel Overpressure

neon

Well-Known Member
Site Donor
Messages
131
Reaction score
32
Location
Newbury, VT
Hello Board - Will not start for more than a few sec after stumbling and barely bringing me home a few wks ago. I tested my pressure just downstream of the regulator after noting a hissing sound coming from the regulator. To my surprise, pressure was about 6 bar, way too high. I am assuming bad regulator, have not tried to adjust. Any thoughts ? Ignition tested Ok based on spark to plugs. Thanks
Dana in CT
 
Be smart here- did you recently jack
your car up in the air? Test both sides of fuel system.
 
6 bars is max output pressure of your fuel pump.
The default of a failed FPR is high pressure.
Thanks ! I have not jacked up the car recently but I disconnected the battery - is the only recent work. I will test the upstream side of the FPR also. If the fuel injectors are seeing 6 bar or thereabouts, would that result in a no start or rough running - rich mixture ? Thanks much Dana in CT
 
Thanks ! I have not jacked up the car recently but I disconnected the battery - is the only recent work. I will test the upstream side of the FPR also. If the fuel injectors are seeing 6 bar or thereabouts, would that result in a no start or rough running - rich mixture ? Thanks much Dana in CT
I think it will result in a fuel leak and possible fire.
I too would look at the return pipe and pressure regulator.
 
Thanks ! I have not jacked up the car recently but I disconnected the battery - is the only recent work. I will test the upstream side of the FPR also. If the fuel injectors are seeing 6 bar or thereabouts, would that result in a no start or rough running - rich mixture ? Thanks much Dana in CT
6 bar is basically three times the specified fuel pressure - yikes! D-Jet is super sensitive to fuel pressure (from what I've learned). I agree with Cornishman, that sounds like a scary situation, especially considering the potential age of the fuel lines, gaskets, etc.
 
if yo check the pressure after the regulator in the return line you should have almost no pressure. If you see any pressure ( or see the high pressure reading) you have a obstruction in the return line . Otherwise change the regulator.
 
Back
Top