I have alfa mito 1.4tb 2008
I have low fuel pressure even after replacing the fuel pump complete original and servicing the injectors sensors are fine
Throttle body is new
Can someone tell me what I am missing
Es esta una buena pregunta?
Rep: 100.6mil
157
87
154
I'm not up on Alfa Romeos, but aren't there two fuel pumps on that car? You've replaced the low pressure pump in the tank, but if I'm not mistaken there should also be a high pressure pump driven by the camshaft; typically it'll be mounted on top of the engine. Along with that should be a fuel pressure regulator, either of which could cause your symptoms.
@imraycooper The way it works on my son's Hyundai is that the pump inside the tank provides standard fuel pressure (something like 60 lbs) to the engine. However, in direct injection engines, you can't squirt fuel under 60 lbs of pressure into a cylinder that's already compressed up to 150 lbs. So it needs another fuel pump to bump that pressure up to something like 1500-2000 psi. The fuel regulator can release pressure in the rail if it gets too high or doesn't need as much pressure at any given time. So there may be a return line to get that extra gas back to the fuel tank when it's not needed.
I use the Torque Pro app (like $5 USD on Google Play), and with that I can see the fuel pressure being reported by the pressure regulator (which in my case is also a pressure sensor). It's hard to measure the high pressure fuel pump's output otherwise; a standard fuel pressure gauge can't handle that high pressure.
Fue útil esta respuesta?
Thans for responding so quickly
I believe the low pressure is built in the fuel pump housing itself but also the other pump is attached to the fuel injectors rail.
It's confusing the he'll out of me..the rail has two side for fuel in and out and it seems to pass through without blockage so I m not sure if the problem is the regulator attached to the rail for injectors
A standard fuel pressure gage can measure fuel tank pump pressures if a fuel rail test port (Schrader valve) is available. As mentioned, low fuel pressure should be around 50-60 psi. High pressures can vary but will around 1500-2300 psi(!) and using a reader capable of displaying the high pressure value is needed. Electronic pressure sensors are used in vehicles with direct injection. Here's some background info; https://www.underhoodservice.com/todays-...
Ultimas 24 horas: 3
Ultimos 7 días: 12
Ultimos 30 días: 44
Todo El Tiempo: 111
@imraycooper how do you know that your engine has low fuel pressure and what pressures do you get?
- de oldturkey03