0.0065psia
0.042 pounds per square inch.
True vapor pressure of distillate fuel oil No. 2 (psi) = 0.0074 + ( 0.00029 ´ ( Average Surface Temperature (deg F) ‑ 60 ) Per EPA publication AP-42
18.6 ATM for diesel UDER ATMOSPHERIC PRESSURE AND TEMPERATURE.
It's right on top of the fuel pump
DVPE is RVP (Reid Vapor Pressure)
its just under 0.5 pounds.
electric fuel lift pump inside fuel tank and high pressure diesel pump on engine driven by timing belt
Vapor lock is a condition when liquid fuel turns to fumes in the fuel system causing it to lose pressure and cause fuel delivery problems. It is not actually a lock.
Because a diesel requires a fuel sprayed under high pressure. Compression on most diesels is over 300 PSI. Injector pressure when the fuel is sprayed can be from 1500-2500 PSI. This is why you need to be careful around diesel lines. The pressure can cut your skin or inject fuel into your body. That can cause problems. A carb can't deliver any pressure.
Fuel tank pressurization is a normal occurrence, caused by temperature change. Even slightly higher temperatures outside the tank than inside cause the fuel to vaporize. Vapor adds to the volume occupied by the liquid fuel. A pressurized fuel tank is a good sign that there are no leaks in your emissions control system. You should find that every time you open your fuel cap a rush of pressure is relieved from the tank. This is because on most cars, fuel that is not used ny the injectors is returned to the tank by the fuel return line. This fuel is warmer than the fuel in the tank, and when the temperature outside is warm or hot, the 2 conditions combined increase the pressure in the tank. Most vehicle have a fuel tank pressure sensor. If your FTP is seeing a higher than normal pressure inside the tank, there may be a blockage of the fuel tank vapor release, or a bad sensor (not probable). Normally, fuel vapor is released to a vapor canister purge valve that sends it directly to the intake system to provide a higher fuel economy, and prevent over-pressurization of the tank. This system, in combination with a fuel tank breather vent keeps maintains a mostly constant pressure.
40-80psi
Both the 5.2 & 5.9 engines should have 49 PSI of pressure (plus or minus 5 pounds), and hold that pressure for 5 minutes after pump cutoff. A "short" drop in pressure can happen with "run tests," but outside these specs shows a problem with the fuel assembly ; located in the fuel tank. (NOTE: these are gasoline specifications, diesel is different).