I have a Fass ddrp 95 thats three years old and I know low pressure is a sign the lift pump is failing. What are other signs? Mine in the last three months has not come on upon start up 4 times and stopped once just after pulling onto street. I have turn it off and on a couple times to it to go. Filters are 2 -3 months old pressure is down a couple psi but it usually is in the winter when it is cold.

I would try changing your filters first. You never know what kind of shmagma can get in there. Anything can happen in 3 months. Also, do you know for 100% that there is full voltage getting to the pump? If it is not getting full power it wont make full pressure. FASS is usually pretty rare to go out. Especially one that is only a few years old.

Other sings are: leaking fuel out of pump somewhere, if it's noisier than usual, pressure drops to low, but yes in winter, especially at 0 and below good chance is it's jelling. But like stated above make sure you have good power to it and relay is working, also make sure connection to ECM is good. I put dielectric grease on all of my plugs.

Is there a relay for that model or does it just plug in to the factory harness? How is it adjustable? If it has a screw with an internal spring perhaps you've got some gunk in there. I would pull it apart and clean and reinstall. Also, it sounds silly, but next time its acting up give the motor a couple of light taps with a hammer. If it takes off and runs good pressure again, chances are either the brushes or motor are on their way out.

Call Fass for some good customer service.  Check all connections for corrosion, clean them & apply silicone di-electric grease. Also, pull the main ECM connector & grease it, then tighten it up.

Ed

So I checked and d grease on all the conection and have had no problems since. Also I re bled the line from the isolator to my ispro gauge and wow I've got pressure. Stupid gauge I have to do that every once and awhile.

What is your technique for bleeding the line?

Get rid of the isolator...

So I checked and d grease on all the conection and have had no problems since. Also I re bled the line from the isolator to my ispro gauge and wow I've got pressure. Stupid gauge I have to do that every once and awhile.

 

 

Get rid of the isolator...

 

#1 reason for loss of pressure is a mechanical gauge isolator. I bet even now if you had a direct plumbed and your isolated gauge you find there is a still a pressure error between them.

#1 reason for loss of pressure is a mechanical gauge isolator. I bet even now if you had a direct plumbed and your isolated gauge you find there is a still a pressure error between them.

 

 

Mike,  have you  done  both  direct and  SNUBBED    at the same time too?  ( same brand of gauges as well)

Edited February 25, 201510 yr by rancherman

Mike,  have you  done  both  direct and  SNUBBED    at the same time too?  ( same brand of gauges as well)

 

My first set of gauges was a DiPricol mechanical gauges. That was direct plumbed with just a needle valve to snub it. Then the new set is ISSPro EV2's which are electric and they are remote mounted on the fender to give distance from the water hammer also needle valve and snubbed with a ISSPro snubber stack after the needle valve. The needle valve in this case is just in case the line breaks I can close the fuel supply off.

 

 

Mike,  all the pics  you've    attached  in the last week or so are only coming up (my end anyway)    with the   little  black square with the 'x'  inside,  and  the   corresponding  jpg  number    When I click on it,  it  doesn't come  up.

 

Other members  attached  pics  seem to be coming  through

Mike,  all the pics  you've    attached  in the last week or so are only coming up (my end anyway)    with the   little  black square with the 'x'  inside,  and  the   corresponding  jpg  number    When I click on it,  it  doesn't come  up.

 

Other members  attached  pics  seem to be coming  through

I get the same at my work computer but at home I see the pictures.  I probably should be doing other things at work anyway.

I get the same at my work computer but at home I see the pictures.  I probably should be doing other things at work anyway.

 

I'm in the same boat as you! Except I thought I was supposed to be doing this at work!

The best way I have found to fill the line from the gauge to the isolator is to use my vacuum break bleeder. I disconnect the line at the isolator and the gauge, I hook up a tube from the gauge end into a jar full of antifreeze, hook up the bleeder to the isolator end of the tube and suck it full. I quickly pull the bleeder off the gauge tube, hook it back up to the isolator, then go do the same thing to the gauge. It gets the tube totally full of fluid. Easy, and from that point on it will stay full because there is no air in it. 

Mike,  all the pics  you've    attached  in the last week or so are only coming up (my end anyway)    with the   little  black square with the 'x'  inside,  and  the   corresponding  jpg  number    When I click on it,  it  doesn't come  up.

 

Other members  attached  pics  seem to be coming  through

 

Those are from my tinypics account.

http://tinypic.com/

 

So...

 

Here it is uploaded here.