Regen question

[crispyboy]

A quick question about the regeneration process.
Tonight I was hooking up a trailer and the truck was idling for several minutes. Out of no where the engine idled up to 900 rpm. The temperature gauge was around 150.

Is this a case of active regeneration at idle?

The exhaust smelled a little funny so I went for a 20 minute ride and kept the rpm up to 1900 by using a lowers gear.

 

[Hoefler]

In a nutshell, no. The engine was not up to operating temperature. What was the outside temperature?? If it had been idling for any length of time, it most likely went into soot reduction mode, not regeneration.

 

[crispyboy]

Out side temp was 74 degrees and very humid. It had been idling for about 10 min which is well out of normal for me.

 

[AH64ID]

900 rpms indicated "Net Reduction" which is a stationary active regen. I though it had to be at operating temp, but maybe 140° is the lower limit??

B. ISSUES IMPROVED SIGNIFICANTLY BY VARIOUS ECM SOFTWARE RELEASES TO DATE:

1/ The latest ECM software includes a new extended idle feature to accommodate the extended idle times present in some duty cycles. This feature may help to reduce the accumulation of soot in the exhaust aftertreatment system when the engine is idling for an extended period of time. Briefly how this feature works:

2/ a. As needed, the engine enters an idling mode which dramatically reduces the rate of soot accumulation in the diesel particulate filter (called “Net Zero”). Further, under extended idle periods of **5 minutes or longer**, the engine enters a mode which reduces the amount of soot accumulated in the diesel particulate filter (called “Net Reduction”). While in these modes, the idle speed increases to 900 RPM for a period of time. The idle speed may return to normal idle speed and then return to 900 RPM to repeat this cycle during very long idle periods.

b. **These modes occur automatically depending on the need to regenerate the DPF as long as the vehicle is not driven over 20 MPH or operated at high load. If the vehicle is driven over 20 MPH normal mobile desoot will occur automatically.**

 

[crispyboy]

Wow ah64id that is some great info. Where did you find it?

I was surprised the truck did this as we pulled our travel trailer some longer distances over the weekend through Indiana. The only thing out of the ordinary was our weekend was interrupted with an emergency road trip to the hospital. My 5yr old daughter broke her arm and we had to high tail it back to Cincinnati and I had to drive a lot faster than I care to mention. Little girls crying can sure rip a daddy's heart out - I promised her a pony on the way to the hospital, I hope she will settle for a goldfish

 

[AH64ID]

It's from the TSB that the flash was released with. All rigs from that point on have it incorporated.

I know what you mean about little girls, I have 3 of them 7 and younger.