Just two hundred hours on a new engine and a sensor fails or did it??

[@JasonHam41]

Credit to you, that is quite the thought process and a good amount of familiarisation on what’s normal and expected. Having been to the Cummins U.K training facility myself for a mid range course, they were very reluctant to share too much on expected values and limitations. Supposedly in case we tried to make a work around of the emissions compliance…. Great video as always. 👏👏

[@stevesauerland223]

Thanks Joe! Knowing good values during Regen really helped on this one as well as using the data in fault snapshots. Seems like I have been replacing quite a few turbo actuators on the HE400 frame turbos lately. Thanks, Steve.

[@ENGINESHOPJOE]

I think they are struggling with heat causing the issues. I have seen coolant line upgrades to increase coolant flow. Another thing we don't always think about is if we have a boost leak or moderately plugged air filter that raises exhaust temperatures all day long so more heat in the turbo. A small shop I help called me and one customer seemed to be having more turbo actuator issues than the others. He ran dump trucks that hauled dirt. I started opening hoods and low and behold most of the air filter minders were at their max limits or close to them. Yes regen history was not stellar either. Now that filter minder is checked every time the units roll into his shop and it has made a difference. They are burning through an air filter about every 3-4 months but other problems stopped.

[@matthewhansen5008]

Yep, most places would have replaced the exhaust gas pressure sensor and sent it on down the road. Y'all did real good in looking closer to determine the actual problem.

[@enchantedwenis4994]

The DPF diff psi jumped out at me initially but I can say it would have taken me awhile to catch the vgt actuator because I never pay attention to turbo speed if my vgt command and actual are within range. I’ve only seen the dpf diff psi max out @10inhg when the turbo is at full boost at idle. But then again I’ve only seen those numbers on units with high mileage and the DPF is typically plugged as a progressive failure. Excellent catch.

[@PeterHodge-l9c]

Joe, im more familiar with Cat and how they use percent/duty cycle as a means of measurement. Often times they'll use a range of say 29% on the low end to 71% on the high end as the normal operating range for a given sensor/switch/actuator. So just to clarify...does the turbo actuator on an X15 use that same kind of parameter or is it a true 0-100% range as viewed through insite?

[@ENGINESHOPJOE]

The VGT assembly has a "0" to "100" physical travel. At 100% closed If mechanically sound it is still open enough for some exhaust gas to exit. In the early day of VGT trucks were towed in with no start and the VGT was stuck at physical 100% and shut the engine down and would not start. Insite would show 160INHG exhaust gas pressure just cranking. Today the VGT can't close that far unless something breaks in the movement linkage. We are talking only about the X15 here not other platforms. The 0-100% is the expected normal mechanical travel of the VGT vane assembly. On highway driving normal VGT ranges will run from 35-85%. Only in a regen will you see 85 to 100% and 100 is not normal. The only exception to this is when engine braking. I have see the turbo at 100% when engine braking going down the highway. I believe the Percentages are accurate position of the VGT when it is mechanically sound. The company I worked for was all cat in the early 2000's but the Cummins was easier to work on as technology progressed and did the job so cat was abandoned. Their parts were also pricey compared to Cummins - at the time. That makes a difference in a 400 tractor and 300 service truck fleet.