Exhaust without a tune

[Chevy1925]

not much, 8 key cylces, maybe 50 miles

you still have time before it codes on ya

not using hp or efi live, im just going by the dtc index as listed on prodemand.

2018 l5p

i was also thinking along those lines, using an exhaust cut out or something like that.

you wont find a DTC for the 700 mile regen. its a system check that will then send a code for something reading different. the computer will then start running self tests to see why regen has not happen. when it never seen an EGT differential, you will probably get codes for inefficient DPF or a bad EGT sensor and so on for nox. i cant tell you what it will throw but dont get specific on the DTC code, look for a generalized dtc that could explain this. remember, the system wasnt built around throwing codes for missing parts, only when things become worn out, damaged, or start failing.

 

[Jakezed22]

you still have time before it codes on ya



you wont find a DTC for the 700 mile regen. its a system check that will then send a code for something reading different. the computer will then start running self tests to see why regen has not happen. when it never seen an EGT differential, you will probably get codes for inefficient DPF or a bad EGT sensor and so on for nox. i cant tell you what it will throw but dont get specific on the DTC code, look for a generalized dtc that could explain this. remember, the system wasnt built around throwing codes for missing parts, only when things become worn out, damaged, or start failing.

thanks, good info here

 

[gmduramax]

Just pull your exhaust off and throw it away. It’ll work just fine.

 

[IdahoRob]

This is one of the reasons that forums have gone down hill so badly. Here's a guy that is trying something different and getting beat up over sharing his thoughts. If this mentality was the norm back in the early 2000's when the duramax started coming around in the performance side of things, not much would of been done. We tried shit and failed many times but this gave the community more data and we came up with ideas. Some worked and some didn't but we mostly worked together.

Like my Mom always said if you can't say something helpful, then shut the he!! up. I can still learn a lot from my Mom.

 

[Jakezed22]

well everyone on the internet is so gosh darn smart its hard to try something new these days!

Anyways, rob have you ever thought of doing an electronic cutout right before the scr? once the mileage ran out a guy could switch it shut, let it regen then open her up again.

 

[SSchmi5519]

well everyone on the internet is so gosh darn smart its hard to try something new these days!

Anyways, rob have you ever thought of doing an electronic cutout right before the scr? once the mileage ran out a guy could switch it shut, let it regen then open her up again.

A cutout set up like that actually might work, for a short period of time...but you'd have to deal with the ECU getting angry every so often and then key-cycling your way out of those codes.

 

[Jakezed22]

A cutout set up like that actually might work, for a short period of time...but you'd have to deal with the ECU getting angry every so often and then key-cycling your way out of those codes.

most of us have a handheld scanner so as long as the codes arent permanment ones should be able to clear them.

by rights should only need to close it every 700 miles for a regen. would be interesting to see what the scr would do with a cut out.

at the very least it would cut down on regens and save some fuel.

 

[gmduramax]

Wait for the truck to regen. Run your cut out 100% open and close it 15% every 100 miles. Might be enough for the truck to think everything is operating correctly

 

[Chevy1925]

How often are you regenning? If it’s an lml we are talking about, you won’t drop fuel mileage any. If it’s an lmm, I’d delete it out of pure fact of how it sends the extra fuel down stream

 

[Jakezed22]

we are talking l5p, if it was a lmm or lml i would just program it.

 

[Jakezed22]

ive read l5p are regening every 200 miles up to every 900 miles

 

[Chevy1925]

we are talking l5p, if it was a lmm or lml i would just program it.

you never specified , that helps a touch. Newbs have a hard time putting threads in the right spot so assuming gets us nowhere.

l5p and diesel usage wouldnt change then, only def usage. if you get a mpg increase, make sure you are hand calcing it and would need to put the equipment back on to confirm the change isnt a placebo affect

 

[Chevy1925]

ive read l5p are regening every 200 miles up to every 900 miles

that vastly depends on your right foot, towing or not and type of driving (highway vs city)

 

[Jakezed22]

i would think if the exhaust isnt going through the dpf then it wont plug and wont regen as often wich would save the fuel being wasted during regen, what do you think?

Agreed the regen interval varies vastly on driving habits.

 

[M.A.M.]

The ECM will command a regen at 815 miles +/- a few miles if the DPF doesn't call for it first.

 

[Chevy1925]

The ECM will command a regen at 815 miles +/- a few miles if the DPF doesn't call for it first.

This

Just got done talking with Josh who broke into and tunes the l5p. He confirmed the same. The truck will do a mandatory regen to self check the system and sensors.

When you hit those miles, let us know what happens

 

[SSchmi5519]

At the end of the day, without a tune there is really nothing to gain besides sound anyway. I don't entirely understand the point. You'll never gain power without adding fuel.

 

[Jakezed22]

This

Just got done talking with Josh who broke into and tunes the l5p. He confirmed the same. The truck will do a mandatory regen to self check the system and sensors.

When you hit those miles, let us know what happens

see theres something i didnt know, thanks

well after only one day i got a P1197 , so the pyros wont stay happy with it off very long. Which rules out a cutout cause you couldnt even make it a day without a light.


Yah theres not a heck of alot to gain with this, but its pretty neat to understand how the system works and hey who doesnt like to here a diesel bark.

Thanks for all the info

 

[Chevy1925]

josh was thinking you wouldnt get past 3-5 key cycles before you got a light. least you made it past that :roflmao:

 

[Jakezed22]

haha! well it would have been pretty close