Q: No pressure after the FPR

asked by on

have a NA 1990 300zx that doesn't seem to be getting fuel past the fuel pressure regulator. I just bought a new pressure regulator and installed it in hopes that would fix the problem but it still doesn't have any pressure past the regulator. When I got the car just about all the rubber in the engine bay was dry rotted so I have replaced all the vaccum, fuel and water lines. I also did aiv, prvr and egr delete to simplify the engine. I have the vacuum line that goes to the FPR going to the plenum as instructed in multiple forums I have read for doing the aiv and prvr solenoid delete. Only thing I can think is that the plenum isn't creating enough vacuum to open the diaphram in the FPR but i dont know how to fix that. I can spray starter fluid in the plenum and the car will start up till it burns off the starter fluid just so you know.
My car has a manual transmission.

The fuel pressure regulator will regulate the fuel pressure by allowing fuel to return back to the fuel tank if the pressure gets too high. If the fuel pump never produces enough pressure and volume of fuel to run the engine, then you need to replace the fuel pump and filter. The vacuum line on the regulator should go direct to the intake behind the throttle plates to work correctly or you will get too high of a fuel pressure when the pump is working.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. No pressure after the FPR

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Can a car jump start with a bad fuel pump?

Jump starting due to a bad battery will not make a bad fuel pump start working. I would recommend replacing a bad battery and then doing a thorough diagnosis of the fuel system to diagnose the fuel pump not working....

Q: Check engine light read 3 maf codes but my car runs perfectly fine should I clean the sensor or replace it ?

The check engine light comes on when there is a failure that can result in increased emissions. This is not always apparent when you are driving. When the controller detects a fault, it substitutes a value for the signal that...

Q: Q: Driver's side window not going up or down.

The Toyota Solara uses a cable type window regulator. As these regulators wear out the will often times move slower and have crunching type noises before they fail. Another possibility is the window motor itself. My advice is to have...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.