12 Valve 2nd Gen Dodge Cummins 94-98 Discussion of 12 Valve 5.9 Liter Dodge Cummins Diesels with P7100 Injection Pumps

slow as hell, 0 pounds boost?

Thread Tools
 
Search this Thread
 
  #1  
Old 01-12-2011, 10:52 PM
Chevy355mark's Avatar
Diesel Enthusiast
Thread Starter
Join Date: Sep 2010
Location: Florida
Posts: 181
Likes: 0
Received 3 Likes on 3 Posts
Default slow as hell, 0 pounds boost?

so i was coming home tonight and the low fuel light was on, it had been on the drive up and the whole drive back from where i was going but the truck was running fine as usual. i catch a mustang at the light and proceed to race him, i boosted it up to about 7psi and launched it, came outa the hole great, ran fine through 4th gear and then it seemed like a sputtered a little so i let out of it asuming im out of fuel. on the drive home i notice the truck is very slugish, seemed like it wasnt smoking much too but its dark and i cant tell. at the light i also noticed it made a noise similar to the sound of a mechanical fan thats stuck on.

so i head to the gas station and put diesel in. after putting diesel in it seemed fine puling outa the gas station, put it in 3rd gear through the parking lot and dumped a reasonable cloud of black smoke, the noise i thought i heard was gone, everything seemed as normall. went to get up to speed and the truck is still very slugish, i put it to the floor and it just struggles through the full rpm range, the noise it makes sounds just like when your lugging a tall gear to make smoke. the motor runs fine, starts up fine, idles good, but it just really feels like it struggles to build rpms. so after all this it finally dawns on me to peek at my gauges, the truck is making no boost at all, 0psi. so i get the truck to about 30mph in 4th gear and put it to the floor, pulled from 1200rpm through 2200rpm, 0psi the whole way and i had reached 1500 degrees egt by the end of the pull, normally i wont touch that kind of egt especially moving that slow.

so i pulled the air filter assembly and checked the turbo, just as always it has absolutely no front to back play, a little side to side and spins free. start the truck up and the turbo spins up fine, sounds fine, the turbo seems to be in great condition really. i have blown the line off the back of the boost gauge before so its possible that i am making boost.

im thinking i may have plugged the fuel filter from running it low, maybe the fuel system is crippled and cant provide the fuel to light the turbo up? maybe i am making no boost due to a blown inter cooler or line? the passenger side batterly leeks acid, maybe it has aten up the intercooler?
 
  #2  
Old 01-12-2011, 11:08 PM
Gbodman's Avatar
Diesel Fan
Join Date: Apr 2010
Location: Minnesota
Posts: 26
Received 1 Like on 1 Post
Default

My money is on an intercooler elbow. High temps, black smoke, no indication of boost. Should be an easy fix for you. It's happened to me a couple of times, scared the hell out of me until I found it though!
 
  #3  
Old 01-12-2011, 11:11 PM
Chevy355mark's Avatar
Diesel Enthusiast
Thread Starter
Join Date: Sep 2010
Location: Florida
Posts: 181
Likes: 0
Received 3 Likes on 3 Posts
Default

i just dont know why this happens when my fuel is low, coincidence i guess. im itching to get on it but its too late. ill find it out in the morning.
 
  #4  
Old 01-12-2011, 11:29 PM
harry22's Avatar
Diesel Enthusiast
Join Date: Aug 2009
Location: small town MN
Posts: 334
Received 27 Likes on 24 Posts
Default

Its done this before, other times when the tank was low?? is that what your saying?
 
  #5  
Old 01-13-2011, 12:26 AM
Chevy355mark's Avatar
Diesel Enthusiast
Thread Starter
Join Date: Sep 2010
Location: Florida
Posts: 181
Likes: 0
Received 3 Likes on 3 Posts
Default

Originally Posted by harry22
Its done this before, other times when the tank was low?? is that what your saying?
no never done this before. i said it ran good like normal. i run it on a low tank pretty often, i just changed the fuel filter but its possible that i could have already plugged it the way i run it so low all the time, especially since cummins use such small filters.
 
  #6  
Old 01-13-2011, 12:09 PM
daveO's Avatar
Diesel Bomber
Join Date: May 2009
Location: Pottstown, PA
Posts: 1,030
Received 171 Likes on 90 Posts
Default

x2 for intercooler boots
 
  #7  
Old 01-13-2011, 12:28 PM
Chevy355mark's Avatar
Diesel Enthusiast
Thread Starter
Join Date: Sep 2010
Location: Florida
Posts: 181
Likes: 0
Received 3 Likes on 3 Posts
Default

blew the boot on the driver side of the intercooler. reinstalled it and dropped the boost down a little and shes runnin better then ever. thanks for the input guys.

does anyone upgrade these boots? i noticed they are very thin and flimsy, the boots on my bros d-max have to be at least 2x as thick.
 
  #8  
Old 01-13-2011, 02:35 PM
daveO's Avatar
Diesel Bomber
Join Date: May 2009
Location: Pottstown, PA
Posts: 1,030
Received 171 Likes on 90 Posts
Default

There are upgraded boots available. Try asking for a quote from one of our sponsors.
 
  #9  
Old 01-13-2011, 02:50 PM
tiremann9669's Avatar
Diesel Bomber
Join Date: Mar 2010
Location: Dansville NY
Posts: 4,233
Received 434 Likes on 356 Posts
Default

I would recomend not runnin so low on fuel also
 
  #10  
Old 01-13-2011, 05:27 PM
Kainedogg's Avatar
Diesel Fan
Join Date: Jan 2011
Location: Shaw AFB\Sumter SC
Posts: 79
Received 2 Likes on 1 Post
Default

Glad you got it fixed friend.
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Un4givn
12 Valve 2nd Gen Dodge Cummins 94-98
10
04-27-2015 01:58 AM
ash23k
Ford Powerstroke 03-07 6.0L
1
12-30-2014 08:31 PM
Tsgbk9
5.9 Liter CR Dodge Cummins 03-07
6
12-23-2014 11:54 AM
joshkhouse80
Ford Powerstroke 99-03 7.3L
1
11-21-2014 01:17 AM
offroad00
12 Valve 2nd Gen Dodge Cummins 94-98
24
10-23-2014 03:28 PM



Quick Reply: slow as hell, 0 pounds boost?



All times are GMT -5. The time now is 03:13 AM.