injector noise?

[F350newbie]

The primary noise you hear when a diesel running aside from the turbo when its going is the injectors or the actual combustion in the cyclinders?

I passed a 350 today on the street with the car and noticed it was very quiet relative to my 350 it looked like a 04 0r 05.

 

[Kleetus]

He may have had a custom tune written for it with the pilot injection turned back on.

 

[ckamp52]

what is pilot injection and y would it be turned off or what have you

 

[Zookie400]

pilot injection is a very small injection event that "warms up" the combustion chamber immediatly before the main injection event. it serves many purposes, most importantly being the lower noise and harmful exhaust emmisions.

the newer common rail systems i am working on currently are capable of 5 injection events per cycle, although only 4 are being used....
1- pilot injection
2- pre injection
3- main injection
4- for dpf regen only, with exhaust valve open, only for dumping raw unburnt fuel onto the cat to "super heat" the exhaust just before it enters the dpf.

 

[Kleetus]

On the early engines, they couldn't keep injectors in them. Many different failure modes, some happened because of garbage quality control. Some of it they traced back to the software and pushing too many operations out of the injectors.

I'm not real sure what the correct answer is, or if it was a comedy of errors.

 

[F350newbie]

Zookie400,

Do 04 F-350 SD have an injection cycle with the exhaust valve open for CAT after burn? If they do what happens when a CAT delete is done? Can the injection cycle for open exhaust valve be turned off?

 

[Zookie400]

im no 6.0 guru... but the post combustion shot is only for dpf regeneration, and the 6.0's dont have a dpf. also, i dont think HEUI injection systems can handle that many injection events per cycle, common rail can however.

 

[ckamp52]

thats cool thanks for the info very interesting i had no idea all that took place always learn something new on here