3rd Gen Engine and Drivetrain -> 2003-2007 5.9 liter Engine and drivetrain discussion only. PLEASE, NO HIGH PERFORMANCE DISCUSSION!

Symptoms of a bad lift pump?

Thread Tools
 
Search this Thread
 
Old 06-05-2006, 03:51 PM
  #1  
Registered User
Thread Starter
 
BigBlueDodge's Avatar
 
Join Date: Mar 2005
Location: DFW, TX
Posts: 331
Likes: 0
Received 0 Likes on 0 Posts
Symptoms of a bad lift pump?

So I finally installed my add on kit for my Quadzilla Commander monitor that will allow me to measure fuel pressure (lift pump) and rail pressure. Install went super smooth. I've had it on a day and need to get some input from you guys. My monitor is showing normal rail pressure numbers, but low fuel pressure numbers (4psi at idle). At this point I'm trying to decide if my lift pump is going out on me. What symptoms should I be looking for to detect a dying lift pump? I've changed the fuel filter but still get the same low numbers.

Thanks.
Old 06-05-2006, 04:41 PM
  #2  
Registered User
 
RickCJ's Avatar
 
Join Date: Dec 2002
Location: Hollidaysburg PA
Posts: 1,170
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by BigBlueDodge
So I finally installed my add on kit for my Quadzilla Commander monitor that will allow me to measure fuel pressure (lift pump) and rail pressure. Install went super smooth. I've had it on a day and need to get some input from you guys. My monitor is showing normal rail pressure numbers, but low fuel pressure numbers (4psi at idle). At this point I'm trying to decide if my lift pump is going out on me. What symptoms should I be looking for to detect a dying lift pump? I've changed the fuel filter but still get the same low numbers.

Thanks.

Low pressure means a bad pump!
Old 06-05-2006, 04:46 PM
  #3  
Registered User
 
stang's Avatar
 
Join Date: Apr 2005
Location: K.S.
Posts: 446
Likes: 0
Received 0 Likes on 0 Posts
What is it at WOT
Old 06-05-2006, 05:10 PM
  #4  
Registered User
Thread Starter
 
BigBlueDodge's Avatar
 
Join Date: Mar 2005
Location: DFW, TX
Posts: 331
Likes: 0
Received 0 Likes on 0 Posts
At WOT it drops down to 1psi
Old 06-05-2006, 05:57 PM
  #5  
Registered User
 
v12xke's Avatar
 
Join Date: Jan 2004
Location: Houston, TX
Posts: 53
Likes: 0
Received 0 Likes on 0 Posts
Not trying to hijack, but how was the install? Is it plug and play, or is it more involved. How many connections? Their web page did not post an installation PDF like for the quad box. Thanks.
Old 06-05-2006, 09:51 PM
  #6  
Registered User
 
03 ant a hemi's Avatar
 
Join Date: Apr 2004
Location: Alberta
Posts: 958
Likes: 0
Received 1 Like on 1 Post
How is your moniter connected to the low pressure side of the pump to tell what your 4 psi is?
Old 06-05-2006, 10:01 PM
  #7  
Registered User
Thread Starter
 
BigBlueDodge's Avatar
 
Join Date: Mar 2005
Location: DFW, TX
Posts: 331
Likes: 0
Received 0 Likes on 0 Posts
Guys, I'd like to give you more information, but I'm a beta tester for this, so I need to keep my mouth shut. I'm sure Quad will tell you more when the time is right. I will tell you that the install is very easy, and will only take you 10-15 minutes at most. The best part is you get lift pump pressure AND rail pressure. The kit comes with all the wires necessary to connect to the Commander modulle. I will say that I was amazed at how fast the rail pressure can get up in to the 20K+ psi range. The Commander module and the fuel pressure sensore are a great product and I highly recommend it. The biggest problem I have is trying to figure out what 4 things I want to show up on the module display.

1. EGT
2. Boost
3. Coolant Temperture
4. Oil Temp/Tranny Temp
5. Fuel PSI
6. Rail Pressure

I put the fuel pressure stuff on this weekend, and am just now seeing what my fuel pressure are in my truck. Its a 2004.5 and has 42K miles on it. I'm thinking I might give the dealer a call and see about a new lift pump. I still have a older style pump, and hopefully can get it switched out to the new in tank pump, if indeed it is bad.
Old 06-06-2006, 09:19 AM
  #8  
Registered User
 
staarma's Avatar
 
Join Date: Jul 2005
Location: Belgrade, Montana
Posts: 2,953
Likes: 0
Received 0 Likes on 0 Posts
10-15 minutes to do EGT and fuel pressure? You are quick. All of those features sound cool for sure. Is it an electrical fuel sensor?

I don't think I would waste my time on a in tank pump. Just go with a pump that will do the job right the first time like the FASS or Walbro, although I have no experience with it it sounds like many people here like it. Do a search on Walbro or FASS to get some more info gathered.
Old 06-06-2006, 10:30 AM
  #9  
Registered User
Thread Starter
 
BigBlueDodge's Avatar
 
Join Date: Mar 2005
Location: DFW, TX
Posts: 331
Likes: 0
Received 0 Likes on 0 Posts
No 10-15 minutes to do the fuel stuff.

I've been giving alot of thoughts to the FASS stuff. But if I can't get mine replaced under warranty, I'll go that route.
Old 06-06-2006, 10:38 AM
  #10  
Registered User
 
Buckshotmckee's Avatar
 
Join Date: Sep 2004
Location: God's Country (Castle Rock, Co)
Posts: 1,489
Likes: 0
Received 0 Likes on 0 Posts
If your looking for more fuel pressure the in-tank update isn't going to make you happy. I understand the fuel pressure on the update is somewhere around 6-7 @ idle and 2-3 @ WOT. If I'm wrong somebody correct me. I'd recommend the FASS only from personal experience.
Old 06-06-2006, 10:55 AM
  #11  
Registered User
 
SBishop's Avatar
 
Join Date: Nov 2003
Location: Choctaw, OK
Posts: 549
Likes: 0
Received 0 Likes on 0 Posts
Your present fuel pump will pass the DC flow test, which is what DC goes by on determining if your pump is good or bad. They only way you will get increased fuel pressures is to go with the FASS or other similar setup.
Old 06-06-2006, 11:02 AM
  #12  
Banned
 
SSminnow's Avatar
 
Join Date: Apr 2004
Location: Pearland, TX
Posts: 1,230
Likes: 0
Received 1 Like on 1 Post
I installed my GDP kit form Glacier (thanks Richard!!!) and I am running my BD on 130HP setting, and when cold, my FP is @ 10PSI, drops to 5 PSI inder boost. When it heats up, drops to 5PSI @ idle @ 1-2 PSI under boost. I have under hood gauge and incab as well. Stock LP on the way out!!!!
Old 06-06-2006, 04:27 PM
  #13  
Registered User
 
staarma's Avatar
 
Join Date: Jul 2005
Location: Belgrade, Montana
Posts: 2,953
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by SSminnow
I installed my GDP kit form Glacier (thanks Richard!!!) and I am running my BD on 130HP setting, and when cold, my FP is @ 10PSI, drops to 5 PSI inder boost. When it heats up, drops to 5PSI @ idle @ 1-2 PSI under boost. I have under hood gauge and incab as well. Stock LP on the way out!!!!
Ummmm...I'm confused. You installed the GDP but your fuel pressure is only 10 PSI and 1-2 WOT?
Old 06-06-2006, 10:36 PM
  #14  
Registered User
 
Spooler's Avatar
 
Join Date: Jan 2006
Location: Claxton, GA
Posts: 5,902
Received 5 Likes on 4 Posts
Where did you install the sendor or Isolator? I have mine after the filter( Banjo under filter can) and before the CP3. I just had my LP changed to the intank unit because of a problem. My pressure was 8 PSI at idle before and after the in tank unit was installed it is now 10 PSI at idle. Before under load the LP PSI was under 4 PSI and now after under load it is 7 PSI. In tank LP helped my truck. No it will not be as good as a FASS or similar but the replacement was under warranty.
Old 06-06-2006, 10:46 PM
  #15  
Registered User
 
Gypsyman's Avatar
 
Join Date: May 2003
Location: Spokane, Wa
Posts: 830
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by staarma
Ummmm...I'm confused. You installed the GDP but your fuel pressure is only 10 PSI and 1-2 WOT?
I was thinking the same thing. Your pressure should be 20 to 22 psi unless you didn't use the regulator in the kit at all. That can't be right...


Quick Reply: Symptoms of a bad lift pump?



All times are GMT -5. The time now is 08:30 AM.