1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

[Soul Asset]

I'm new to this forum. I have a 1998 Volvo Penta 5.7L GSi that will not run correctly, seemingly due to fuel issues. :facepalm: I replaced the high pressure fuel pump yet it still reads 12-13 and drops. Both fuel pumps activate with ignition. The engine will start fine but will not sit at idle. It will continue to run if the throttle is pumped. I've checked the filter but did not find water, although the problem started shortly after fueling. Not sure where to start. At first the engine would idle fine but bog under load, now it it won't even idle correctly.
Is it possible that the IAC could be at fault? Any help with a checklist (in order) would be greatly appreciated.
Tom

 

[Don S]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

You can't get good fuel pump pressure if you can't get fuel to the pumps. Here is some testing you need to do before you throw any more parts at it.
http://forums.iboats.com/showthread.php?t=283269

 

[Soul Asset]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

I've conducted the tests with a clear hose, as well as ran the engine with fuel from a seperate tank, yet it does the same thing. Also, the lines will not hold pressure once they are charged, and the newly replaced high pressure pump only reads 12-13 lbs...essentially the same as the low pump.
Is it possible that something in the fuel reservoir, below the high pressure pump, is causing this problem? The reservoir contains a float mechanism, much like a carberator.
Also, could the pressure regulator or the Throttle position sensor cause these symptoms?

 

[Don S]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

Are you sure the high pressure pump is even running? an easy test is to unplug the low pressure pump, turn the ign. sw. on and see if you can hear the pump run for 2 seconds. It's not going to build up any pressure if it doesn't run.

What is the FULL model number or even the serial number of your engine, year doesn't mean anything.

 

[Soul Asset]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

Volvo Penta 5.7L GSi # 4110180279

 

[Soul Asset]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

I disconnected the power to the low pressure pump and turned the ignition. The high pressure pump DID respond for 2 seconds.

 

[Don S]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

Great, if anyone asks again, your FULL model number is 5.7GSIPWTR the WT is the model and is basically a 99 model.
Go to this link for manuals http://forums.iboats.com/showthread.php?p=2360521#post2360521

 

[Soul Asset]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

I disconnected the power to the low pressure pump and turned the ignition. The high pressure pump DID respond for 2 seconds.

 

[Don S]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

Did you download the manuals yet?

 

[Soul Asset]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

yes

 

[Don S]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

Go to the EFI Diagnostic manual, and start on page 6-16 Chart A-4

 

[Soul Asset]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

Don, We've concluded that the Fuel Pressure regulator is faulty. We determined this by plugging the line OUT, from the pressure regulator to the reservior, and received adequate pressure on the high pressure linewhen it was plugged. The conclusion is that the pressure regulator is not preserving pressure, rather allowing fuel to slip back to the reservior below the high pressure pump.
Now, Next hurdle is locating a new fuel pressure regulator because it has been discontinued. Perhaps you can help me identify a replacement for it. It is part number 3856395. I went to a Volvo Penta dealer and they could not locate a replacement part number. Any help would be greatly appreciated!
Tom

 

[Soul Asset]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

Cannot locate a discontinued part for my boat. It is part number 3857397 (a repair kit for the fuel pressure regulator) Any ideas? I've been looking online for days

 

[cobalt1999]

Re: 1998 Volvo Penta 5.7L GSi - Fuel issues, or is it?

according to Marine Parts Express 3857397 has been replaced by 3861279.....