When does fuel pressure drop after turning off the engine?
Turn the engine off, but key on and pressure gradually drops all the way to 18 PSI over 20 minutes. Turn the key off then key on but no engine start, I can hear the 2 second fuel prime and the PSI shoots up to 55 PSI and engine still has to turn over for 3 or 4 seconds without gas pedal, 1 or 2 seconds with gas pedal.
What happens to fuel pressure when you turn the key off?
SOLVED: Fuel pressure bleeds off when i turn the key off . – Fixya Hooked a fuel pressure test up . the pressure pops up to 55 to 58 psi. i turn key off pressure drops down to 15 20 psi Clicking this will make more experts see the question and we will remind you when it gets answered.
What does 0 psi mean on fuel gauge?
CASE 2: The fuel pressure gauge’s needle DID drop down to 0 PSI immediately after the Key was turned to the Off position: This tells you that there is something leaking inside the plenum. More than likely, it’ll be the fuel pressure regulator, to make sure go to: TEST 2.
What should the fuel pressure be on a GMC Sierra?
Drives:2004 GMC Sierra Posted October 8, 2010 When the ignition switch is ON and the fuel pump is running, the fuel pressure indicated by the fuel pressure gauge should read 379-427 kPa (55-62 ps i). The spring pressure inside the fuel pressure regulator controls the fuel pressure.
What happens when fuel pressure drops to 0?
Or the fuel pressure gauge’s needle will immediately drop to 0 PSI. If the fuel pressure drops down to 0 PSI within seconds, then you’ve got a problem. In a system where the fuel pressure regulator or fuel Lines are not leaking, the pressure should hold steady (not dropping to zero) for about 5 minutes.
What should the fuel pressure be on a Chevy Silverado?
If you want to save some bucks on this purchase take a look at my recommendations here: Where To Buy A Fuel Pressure Test Gauge. FUEL PRESSURE SPECIFICATION: The fuel pressure specification for the 1999-2006 4.8L, 5.3L, 6.0L Chevrolet Silverado (Suburban, Tahoe) and GMC Sierra (Yukon, Yukon XL) is 55 to 62 PSI. Flex fuel engines: 48-54 PSI.
CASE 2: The fuel pressure gauge’s needle DID drop down to 0 PSI immediately after the Key was turned to the Off position: This tells you that there is something leaking inside the plenum. More than likely, it’ll be the fuel pressure regulator, to make sure go to: TEST 2.
What to do if your fuel pump looses pressure?
To check the fuel pump, presurize the fuel system and only block off only the return line. If it holds pressure then you know the the fuel pump is ok and the problem may be with the fpr. If you loose pressure, the pump check valve is bad and you need a fuel pump. To check the fpr, pressurize the system and then block off only the feed line.
How does the fuel pump know when to shut off?
Some vehicles can vary the voltage to the fuel pump to control fuel pressure. In the case of an accident, there are many crash sensors on modern cars that the PCM will monitor. When an accident has been registered, the PCM has the option to cut power to the fuel pump by turning off the fuel pump relay. Was this answer helpful?
What happens if you have low fuel pressure?
Today’s electronic cars have a fuel pressure sensor that intelligently calculates if anything is going wrong. If it is, the sensor triggers the check engine light prompting you to get your fuel system checked. Generally, with such a problem you will get a P0190 code accompanying your problem.
Why is my fuel pump not producing pressure?
The fuel pump is able to create pressure using electricity but if it is not getting the adequate voltage of electricity it will not be able to function properly. Consequently, the fuel will not be released at the perfect pressure and your car will lose efficiency.
Turn the engine off, but key on and pressure gradually drops all the way to 18 PSI over 20 minutes. Turn the key off then key on but no engine start, I can hear the 2 second fuel prime and the PSI shoots up to 55 PSI and engine still has to turn over for 3 or 4 seconds without gas pedal, 1 or 2 seconds with gas pedal.
SOLVED: Fuel pressure bleeds off when i turn the key off . – Fixya Hooked a fuel pressure test up . the pressure pops up to 55 to 58 psi. i turn key off pressure drops down to 15 20 psi Clicking this will make more experts see the question and we will remind you when it gets answered.
Some vehicles can vary the voltage to the fuel pump to control fuel pressure. In the case of an accident, there are many crash sensors on modern cars that the PCM will monitor. When an accident has been registered, the PCM has the option to cut power to the fuel pump by turning off the fuel pump relay. Was this answer helpful?
What happens if the fuel pressure regulator is not working?
If the fuel pressure regulator is not maintaining exact fuel pressure while the engine is running, it can cause the engine to run rich or lean, and in the event it goes too far in either direction, the engine will stall out due to an inability to properly burn the air/fuel mixture.