Volvo 5.0 GL fuel system question.

[Tidewater21]

I have a 99 regal lsr 2100 with the 5.0 GL engine. I am getting no fuel from the pump. I have tested the pump,breaker and relay. Everything tests out ok. Read on a forum there is a diode that may be open. Cannot find this diode. Any help would be appreciated.

 

[Don S]

Re: Volvo 5.0 GL fuel system question.

What is your engine doing? Starting and stopping, not starting? What.

 

[Tidewater21]

Re: Volvo 5.0 GL fuel system question.

Will not start at all unless you manually put gas in carb.

 

[Don S]

Re: Volvo 5.0 GL fuel system question.

Perhaps these 2 threads will help you figure out the problem.
This one explains how the fuel pump system works.
http://forums.iboats.com/showthread.php?t=547983&p=3761225&viewfull=1#post3761225

This one shows you how to troubleshoot it the system.
http://forums.iboats.com/showthread.php?p=2715541#post2715541

 

[Tidewater21]

Re: Volvo 5.0 GL fuel system question.

Thanks I'll read them and give that a try. I will get back and let you know what I found. Thanks for the quick response.

 

[Tidewater21]

Re: Volvo 5.0 GL fuel system question.

Just finished tracing the yellow/red wire from the ignition to motor. Found it went to another relay behind the 2 50 amp breakers. Will test it and see from there.

 

[Tidewater21]

Re: Volvo 5.0 GL fuel system question.

Everything tested ok until I got to the alternator. The wire going from the alternator to the fuel pump was showing 2 volts with the switch on and 3 volts when cranking. Took the alt off and going to have it tested tomorrow. Maybe this is the culprit.

 

[Don S]

Re: Volvo 5.0 GL fuel system question.

Probably not your problem. That green wire does nothing until the engine is running and the alternator charging. If you are just sitting there with the key in the run position, the pump better not run. But if you take that green wire off the alternator and with a jumper wire hooked to the green wire touch the battery positive terminal and the pump should run.

PS, that other relay is the starter slave relay.

 

[Tidewater21]

Re: Volvo 5.0 GL fuel system question.

After doing a lot of testing found the battery had a bad cell and the alternator was only putting out 2 volts at the fuel pump pin. Replaced both and engine runs great. Thanks Don for your help.