Exhaust Braking while have Boost

[Big MAK]

Last year when I'd hook up my 5th wheel and travel I would never get exhaust braking at the same time as boost - this year I've seen as much as 12 lbs of boost while simultaneously having 150 bhp. And yes.. you can hear the engine working against the exhaust brake (zero throttle being applied of course). Just had routine services done and dealer reports no issues found and there are no codes being thrown. Getting 2-5 lbs of boost while exhaust braking happens almost every time the brake engages.

After some contemplation I suspect the EGR system is routing partially spent fuel back into the intake side causing this scenario, and perhaps I didn't notice it last year because I didn't tow in colder weather.

Nevertheless this has me a little perplexed. Anyone else observe this phenomenon? Anything amiss?

Final note: Recently back to TDR and if there's any other old-timers out there they know I've modified the heck out of a lot of diesel engines. This rig is darn near perfect out of the box. Dodge/Cummins did good Still bone stock. The only thing I want to "fix" is the throttle lag.

 

[Hoefler]

Perfectly normal. As the exhaust is restricted, it will cause the turbo spool up and build pressure. Causing more air to go into the cylinder to compress and no place to go. There is no fuel being used and the engine works as a compressor absorbing energy.

 

[kleinbus]

If you set you display to "turbo", it will show you the braking power at given EB moment.

I have come down the Rockies on 3rd with full EB boost and it's what its made for....

 

[Big MAK]

Yep that's what I do - it's set on turbo at all times. Old habits... used to have full gauges as my first upgrade to my Cummins, always watch the boost to see if it's where it should be (early leak warning).

 

[Newsa]

I have seen Banks EB & Pac Brake mentioned on here by people who have owned previous versions of (previous gens) of Ram Cummins.
Was any type of EB provided as factory standard equipment, or a factory option on previous gens?

A buddy of mine who ran a second gen 500,000 miles, was shocked to hear that all 4th gens come standard with an EB. When he heard my truck has an EB, he asked how hard it was to install. He never put one on his. I explained it comes standard nowadays.

I believe we actually benefit from the emissions of the 4th gen (even though the 4th gen emissions seems to be a liability with all the parts that could go wrong). The only reason (I can figure why) our trucks come standard with an EB is because it applies the load required for an active regen.

Another question that I have is about the Cummins 5.0 on the Nissan Titan. The 5.0 doesn't have an EB.
It does have a DPF. How does the 5.0 do an active regen without an EB to apply the load?
Does it have another method of burning out the soot????????

 

[Newsa]

Sorry, duplicate post. Trouble with my mini pad