GMC Truck Forum banner
1 - 17 of 17 Posts

·
03 Silverado in progress
Joined
·
692 Posts
Discussion Starter · #1 · (Edited)
Alright forgive me for not having exact specifics but i'm trying to help my buddy out. He has a 04 D-max 2500 with an Edge Evo programmer, K&N intake, and custom mandrel bent exhaust with no cat, and bully dog injectors. He has taken the truck to three different mechanics and gotten three different answers. I told him to post it on gmfullsize but he's so pissed off he wouldn't listen. Anyway the thing is idling real rough (going from 700 for half a second then up to 1000RPM for a split second then back down to 700). Plus the MPG has gone down like two to three mpg. I was thinking that the injectors are going bad and dumping fuel. What do yall think?:think:
 

·
concrete *******
Joined
·
1,923 Posts
first thing you want to do is check the oil and see if there is fuel in there. then you will want to have the ballance rates checked. also is it an LLY or LB7?

also are you sure about the bully dog injectors?
 

·
03 Silverado in progress
Joined
·
692 Posts
Discussion Starter · #3 ·
LLY and yes they are bullydog injectors....is is true there is a special tool to change those injectors that cost like 500 bones?
 

·
concrete *******
Joined
·
1,923 Posts
not that i've ever heard of. the LLYs are easy too, prolly around 6 hrs.

who did he get these "bully dog" injectors from?
 

·
03 Silverado in progress
Joined
·
692 Posts
Discussion Starter · #5 ·
some guy out in Utah about two years when he was doing some work out there........do you think the injectors are going bad or could there be another problem?
 

·
concrete *******
Joined
·
1,923 Posts
i would bet hands down it's either the injectors or the CP3 reg
 

·
03 Silverado in progress
Joined
·
692 Posts
Discussion Starter · #7 ·
is it common for injectos to only go out after two years?........are there any that you would reccomend
 

·
Mike D
Joined
·
53 Posts
for one he has no need for aftermarket injectors. hes not running nearly enough power to where they would make any difference. stock injectors can handle big power levels just fine. that being said i agree with Kyle, its most likely either the injectors or the fuel pressure regulator. is his an 04 LB7 or 04.5 LLY? that makes a big difference as the LB7's are the ones where injectors are most common.

and yes, LB7 injectors can go at any time. there really doesnt seem to be a ryhme or reason to when they go and how long they last. ive been lucky so far and am on my stock ones at 133K but ive heard of plenty of guys going through 3 or more sets in that time.
 

·
concrete *******
Joined
·
1,923 Posts
X2^

if he needs new injectors give me a shout, i can put him into some DDPs and actually increase his mileage as well.
 

·
Registered
Joined
·
505 Posts
It does sound like the injector(s) is/are going bad. Also, I'd tell him to get a tuner that actually accounts for the bigger injectors.
 

·
concrete *******
Joined
·
1,923 Posts
only thing that would be is EFI.
 

·
Registered
Joined
·
505 Posts
unless you run out of smoke
 

·
concrete *******
Joined
·
1,923 Posts
actually, bigger / better injectors will not only get you better fuel mileage, but, in most cases depending on your set up, lower EGTs as well.
 

·
concrete *******
Joined
·
1,923 Posts
nope even still. something like a 50hp nozzle from DDP will get you about 1-2mpg increase, even if you had a superchips.
 

·
Registered
Joined
·
505 Posts
I'm getting worse mileage right now since I got bigger injectors. The truck pulls a lot harder but I'm pretty sure it was not worth it.
 
1 - 17 of 17 Posts
Top