Fuel pressure issue

[kxhonda]

I have a 150gph HPFP on my truck and and just recently my fuel pressure is really starting to drop when WOT. I just replaced the inline prefilter and main fuel filter and it's still the same. When I'm on it hard it drops down to 7-8 psi and when I sled pulled this weekend it was down to 4-5 psi. It started popping bad when the fuel pressure went down that low. Idle is at 14psi.

Is this pump on its way out or do I have something else going on? Is there a different spring I can put in there? The Serial# is 7876.

 

[Diesel-Dan]

I have a 150gph HPFP on my truck and and just recently my fuel pressure is really starting to drop when WOT. I just replaced the inline prefilter and main fuel filter and it's still the same. When I'm on it hard it drops down to 7-8 psi and when I sled pulled this weekend it was down to 4-5 psi. It started popping bad when the fuel pressure went down that low. Idle is at 14psi.

Is this pump on its way out or do I have something else going on? Is there a different spring I can put in there? The Serial# is 7876.

Well with pressure issues (And im going to sound like a broken record here), i always like to confirm the gauge is telling you the truth. If you have an isolator or electric gauge in there, you might start by looking at those first.

You are not running out of fuel as far as our pump goes...as you kept positive pressure on your pump as per the gauge. So i dont think that would be an issue there. Its low, yes...but it shouldn’t be causing any fueling issue.

When you replaced the inline filter...did you get a filter or strainer? We recommend the NAPA 3270 inline strainer for the HPFP's. If you used a filter, this could cause issue with pressure as well. Might check what you have in there.

If all that checks good, try pulling fuel out of a container and see if the pump sounds any differant or the pressure is more solid.

Let me know what you find and we can go from there.....

 

[kxhonda]

Its a mechanical gauge with no isolator. And I temporarily ran another gauge through the window with the same results.

It was a Napa 3270 that I replaced it with. I will try pulling fuel out of something other than tank tonight.

 

[kxhonda]

Alright well I tried pulling diesel out of a gas can tonight with the same results. No improvement in pressure. But while I was under there checking some stuff I noticed the pump was making a squealing/screeching sound intermittently. Maybe sounded like a bearing or something.

 

[Diesel-Dan]

Alright well I tried pulling diesel out of a gas can tonight with the same results. No improvement in pressure. But while I was under there checking some stuff I noticed the pump was making a squealing/screeching sound intermittently. Maybe sounded like a bearing or something.

Bearing would not squeal, per se...when they go bad...they grind like no other....you would know something is up if that was the case.

Its prob the pressure spring in the pump. We have had thoes resonate from time to time...and considering the age of your pump, you might not have the updated base that keeps that from happening. (Just holds the spring tigheter).

Might have your dealer contact me about this and we can see what we can do.

 

[kxhonda]

Pump is only a year old. If it is the spring that is resonating, is this also the cause of my low fuel pressure? And also, is there a diff spring to get me up to around 20ish psi?

I will be contacting Diesel Nut Motorsports here shortly to see what we can do.

Thanks
Eric

 

[Diesel-Dan]

Pump is only a year old. If it is the spring that is resonating, is this also the cause of my low fuel pressure? And also, is there a diff spring to get me up to around 20ish psi?

I will be contacting Diesel Nut Motorsports here shortly to see what we can do.

Thanks
Eric

Ahh...Jason...good man there...have him call me and we will lay out some options.....