04 monaro no fuel pressure

[sheepdip]

I have fitted the running gear from a 04 monaro in a mk2 escort. It has ran great for over 10 years now. But the other month I noticed it was needing to crank more than usual. As I have a fuel pressure gauge fitted I noticed that it was not holding pressure and it dropped off as soon as the pump was turned off where as before it would hold pressure for weeks between running. I took the pump out of the tank but was unable to strip it without the risk of damaging it so just put it back. I guessed a none return valve within was passing. Now the car has failed to start a couple of times as no pressure with the pump running. Help please with a diagram so I can strip the pump down. Or where I can get a replacement please. Cheers all

[Lincsls1]

These should be the right pump (big boot V2 2004 Monaro)...

https://www.ebay.com.au/itm/HOLDEN-HSV-Monaro-V2-2...

https://www.ebay.co.uk/itm/144972279619?mkcid=16&a...

[stevieturbo]

sheepdip said:

I have fitted the running gear from a 04 monaro in a mk2 escort. It has ran great for over 10 years now. But the other month I noticed it was needing to crank more than usual. As I have a fuel pressure gauge fitted I noticed that it was not holding pressure and it dropped off as soon as the pump was turned off where as before it would hold pressure for weeks between running. I took the pump out of the tank but was unable to strip it without the risk of damaging it so just put it back. I guessed a none return valve within was passing. Now the car has failed to start a couple of times as no pressure with the pump running. Help please with a diagram so I can strip the pump down. Or where I can get a replacement please. Cheers all

Did you use the actual Monaro tank ?

Pretty much any generic Walbro would do really. 255-340 or so.

Can you hear the pump running ? Like no pressure whatsoever, or low pressure ?

[sheepdip]

Hi Steve
I used the the full pump unit in a one off fabricated tank. Hence use the level sensor and pressure regulator. Pump runs as it should via ecu. But it stopped holding pressure after the engine is turned off so guessing the regulated return line started passing as no leaks in the high pressure side but now some times the engine will not start as no pressure but pump is running so guessing the regulator is not regulating! Guessing there could be some contamination in the regulator? Lots of guessing.

[stevieturbo]

sheepdip said:

Hi Steve
I used the the full pump unit in a one off fabricated tank. Hence use the level sensor and pressure regulator. Pump runs as it should via ecu. But it stopped holding pressure after the engine is turned off so guessing the regulated return line started passing as no leaks in the high pressure side but now some times the engine will not start as no pressure but pump is running so guessing the regulator is not regulating! Guessing there could be some contamination in the regulator? Lots of guessing.

Stop guessing, start testing.

Could be a hose issue in-tank, could be the reg, could be the pump, etc etc.

[sheepdip]

I have taken the pump unit out of the tank but unsure how to take it apart to conduct further testing. I did not want to damage the plastic housing hence asking for advice. Have you ever removed the pump if so how please. Or removed the regulator as that must live inside too.

[stevieturbo]

Are any of the hoses split or damaged ? especially any hard nylon types ?
What does the pump inlet filter look like ?

[sheepdip]

All looks good and when the pump is running its giving the pressure. Sure its the regulator but as I have said not sure how to get at it. think its a sealed unit. Anyway I have order a new pump assembly so will wait for that to arrive before stripping the pump out the tank again.