Chevy and GMC Duramax Diesel Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
6,215 Posts
Discussion Starter #1
Ive Got a few questions that I've never been clear on.
How does pilot injection work to make the engine quieter?
If I want to turn it off with efi, what do I do? Set all of the pilot injection tables to zero? Does it do damage to anything if turned off?
I've only made a few minor tunes with efi, so I'm still not sure what does what and I need some clarification!:help
 

·
Registered
Joined
·
6,193 Posts
its a small spray on the up stroke of the cycle. not sure how exactly it causes a quiter idle. but you dont want to turn it off. your truck will sounds like crap.
 

·
Registered
Joined
·
6,215 Posts
Discussion Starter #3
its a small spray on the up stroke of the cycle. not sure how exactly it causes a quiter idle. but you dont want to turn it off. your truck will sounds like crap.
No, I want to! Lmm's sound like turbocharged sewing machines...even straight piped!
I read something about incresing timing and sometimes increasing the main injection if necessary. Also read about turning it off at idle so it only sounds that way until you rev to xxxxrpm. That way performance isn't sacrificed.
I'm trying to figure this out.
 

·
Registered
Joined
·
6,193 Posts
go to youtube and listen to trucks that are running no pilot injection, then come back here and honestly say you want your truck to sound like that
 

·
Registered
Joined
·
312 Posts


No thanks.
 

·
Less than desired
Joined
·
992 Posts
Sounds like some shit is about to fall out the bottom! Don't do that!
 

·
Premium Member
Joined
·
17,806 Posts
Your neighbors will hate you! LOL
 

·
Registered
Joined
·
1,046 Posts
Set them to zero, and see what you think? That's how you turn it off.
I'm not by my computer or I would tell you which ones to mess with.


Sent from my Autoguide iPhone app
 

·
Registered
Joined
·
377 Posts
Pilot helps with premixing the fuel and air. Creating a "better" combustion event, that is why it is in place, not sure how it actually works to reduce noise, but it does. It shouldn't hurt anything to turn it off, it turns off at higher rpm anyhow...
 

·
Banned
Joined
·
5,738 Posts
The pilot injection also lessens the harshness of the lockup when you shut the engin off, which in turn creates less wear on your main bearings. Leave them..........
 

·
Registered
Joined
·
377 Posts
Just out of curiosity, where does that little bit of knowledge come from?
 

·
Banned
Joined
·
5,738 Posts
Just out of curiosity, where does that little bit of knowledge come from?
GM, when I complained about the annoying squeak from the fan belt they reflashed it. It stopped squeaking imediately and it is my opinion that violently stopping an engine is worse for the bearing surfaces than slowly allowing it to stop.
 
1 - 14 of 14 Posts
Top