Lb7 with no low end power - Diesel Place : Chevrolet and GMC Diesel Truck Forums
 
Home Forum Market Place Garage Tuning Library DTC Tool Register Vendors
Go Back   Diesel Place : Chevrolet and GMC Diesel Truck Forums > GM Diesel Engines > Duramax First Generation: 2001-2004 (LB7)
Register FAQ Forum Rules My Replies My Threads Mark Forums Read Advertise

Duramax First Generation: 2001-2004 (LB7) Discuss the first generation (2001-2004 LB7) of the 6.6L Duramax diesel engine & associated components. Engine related discussion ONLY.

DieselPlace.com is the premier Duramax Diesel Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools
Old 01-09-2020, 03:48 PM   #1 (permalink)
srhodes
Low Boost
 
Join Date: Jan 2020
Posts: 5
iTrader Score: 0 reviews

Lb7 with no low end power

I have a 2002 Chevy 2500hd lb7 duramax (on my phone and can’t fill out the sig) efi live tuned by ridge runner, stock trainer, banks wastegate, new cp3 with less than a couple thousand on it. Injectors were pulled and rebuilt when I bought the truck two years ago.
It started august of 2018 when my truck got hot while towing my camper, motor and tranny got between 215-230. When we got home and realized the inter cooler lines were tightened all the way snug which probably cause my problem. Within a week I blew the bottom tranny line on the freeway and had to get towed back home. But my the time we got home I think the tranny way about out of fluid. Refilled it and went on but now fast forward from that point, the truck Has a hard time building boost under 2000 rpms, once it hits about that 2000 rpm range it takes off and throws you back in the seat. I’ve checked boost lines, replaced cp3 thinking that might be the problem, added a fass lift pump. I don’t want to throw any more money at things that aren’t working. The last thing I can think of is maybe bad MAF sensor but I’ve pulled it out and cleaned it 3-4 times since August 2018. Any help is appreciated

__________________
2002 Chevy 2500hd lb7 duramax
efi live tuned by ridge runner, stock trainer, banks wastegate
fass lift pump
Offline  
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 01-09-2020, 04:01 PM   #2 (permalink)
OkDually
Administrator
 
OkDually's Avatar
 
Join Date: Jul 2013
Location: N.E. Oklahoma
Posts: 14,554
iTrader Score: 0 reviews

DieselPlace.com Lifetime Premium Member

Checked for any codes?

__________________
1996 K3500 6.5L,( "F" Eng #141 cast block) 5 speed manual, crewcab, dually longbed: 208,000mi.
Diamond Eye 4" Turbo Back Exhaust w/2.5" Flo-Pro Crossover
AirDog II DF165 w/ tank sock delete - XDP
TD-Max boost controller - Kennedy Diesel
OPS extension hose - Leroy Diesel
Glow Plug Harness- PT Wiring Solutions
Glowshift Maxtow EGT,Boost, Fuel gauges
Boost & Fuel Pressure Bolts - Leroy Diesel
2/0 Battery Cable Upgrade - PT Wiring Solutions
PMD w/#9 resistor and Re-Location Kit, mounted to bumper - Leroy Diesel
GM-5 Turbocharger
4.10 gear ratio
OptiLube Winter Formula


Proud member #1039 of The 3500 Dually Club

Online   Reply With Quote Quick reply to this message
Old 01-09-2020, 07:39 PM   #3 (permalink)
srhodes
Low Boost
 
Join Date: Jan 2020
Posts: 5
iTrader Score: 0 reviews

Checked for codes with nothing pending or setting off check engine light.
__________________
2002 Chevy 2500hd lb7 duramax
efi live tuned by ridge runner, stock trainer, banks wastegate
fass lift pump
Offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 01-09-2020, 08:13 PM   #4 (permalink)
srhodes
Low Boost
 
Join Date: Jan 2020
Posts: 5
iTrader Score: 0 reviews

I have an edge CTS 2 monitor and when checking the engine load at idle is about 25-35%
__________________
2002 Chevy 2500hd lb7 duramax
efi live tuned by ridge runner, stock trainer, banks wastegate
fass lift pump
Offline   Reply With Quote Quick reply to this message
Old 01-10-2020, 09:25 AM   #5 (permalink)
Rvn4me
Diesel Pro
 
Rvn4me's Avatar
 
Join Date: Jun 2016
Location: MI.
Posts: 2,398
iTrader Score: 0 reviews

Michigan Oil Burners Member

When was the last time you changed the fuel filter and air filter? Any smoke? Stock air filter? Does this on all levels? Have you date logged to see what’s going on? What does ridge runner say?
https://www.dieselplace.com/forum/63...end-power.html
https://www.dieselplace.com/forum/63...end-power.html
Google (Duramax Lb7 no low end power) lots of info. Maybe you’ll find something.

Last edited by Rvn4me; 01-10-2020 at 09:40 AM.
Offline   Reply With Quote Quick reply to this message
Old 01-10-2020, 03:55 PM   #6 (permalink)
srhodes
Low Boost
 
Join Date: Jan 2020
Posts: 5
iTrader Score: 0 reviews

20 lbs of boost at wide open throttle getting on the freeway. As soon as the torque converter locks in 5th gear the boost goes from 15-20 down to less than 5 in a matter of 2 seconds. No smoke, as I turn up the tuning it gets even more bogged down and sluggish on the low end but spools the turbo a lot quicker once it’s gets into that higher rpm range. Fuel filter a couple months ago and less than 5k miles on it. Changed it in hopes it would help reading so many people mentioning it but no help. Air filter about a year ago. I will try to change that. Ridge runner made me sent them wot throttle pulls. I was thinking it was the cp3. They thought it was the wastegate. Replaced it with a banks wastegate and set to about 7 turns. I’ve never heard a good number for how much turns/preload to set on it for everyday driving.
At about 65 on the freeway I’m at about 0-2 lbs of boost maybe. I have to give it about half throttle to even get it to move. Even at that once I’m driving I can only get about 5 lbs while trying to increase speed. If I floor it it spools the turbo quick but doesn’t shift down and as soon as I let off the gas peddle it’s like I loose all the momentum and boost I just built.
__________________
2002 Chevy 2500hd lb7 duramax
efi live tuned by ridge runner, stock trainer, banks wastegate
fass lift pump
Offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Diesel Place : Chevrolet and GMC Diesel Truck Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

PLEASE READ! You must check your email inbox for the confirmation link to complete registration. Please check your spam box if you do not see the email in your inbox.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Insurance
Please select your insurance company (Optional)

Log-in


Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -4. The time now is 10:13 AM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Shoutbox provided by vBShout v6.2.1 (Lite) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd. Runs best on HiVelocity Hosting.
© AutoGuide