This EGR Valve fault code popped up and it caused a slight hesitation on acceleration which would make sense if the valve is open at the wrong time. The EGR funnels cooled exhaust coming from the EGR cooler into the intake system to cut down on emission levels. The code was 1896 EGR Valve Controller out of calibration.
In the end we replaced the EGR valve after checking the harness and connector for poor continuity and proper battery voltage levels. It’s an 8 pin connector with a 5 volt supply voltage, ground return and 6 other circuits working the EGR position and motor. What caused the code was a failed automatic calibration procedure that is actuated every time the ignition key is on or while the engine is running.
The EGR valve motor measures the EGR valve position when the ignition is first turned on. More than a 20% opening at the EGR valve will trigger this fault code. Immediately the amber check engine light will come on after the diagnostic test fails. Then the EGR valve will not respond to commands and the built in spring mechanism will close the valve.
Once repaired the ECM will turn off the fault code when the diagnostic check passes. Some of the procedures for checking this problem out is to make sure the ECM is calibrated which can be verified by looking up the engine serial number on Quickserve to see if all revisions have been completed.
Cummins recommends checking the aftertreatment system after the repair has been made. A snap acceleration test will test the diesel particulate filter. On our bus everything checked out fine and it ran like a dream. In the video the location of the EGR valve made it dead easy to get to. This is the way it should be…if there are any engineers that know what they’re doing you will find them at the Cummins engine plant.
Regular maintenance engine parts need to be accessible the competition couldn’t care less about design. I don’t want to pull out the pedestal but I have to say whenever anyone asks me what medium duty diesel engine would I recommend it’s always the Cummins ISB 6.7 Liter. They rarely fail and if they do it’s expensive but every emission controlled diesel on the market today costs a pretty penny to keep on the road.
The EGR valve we replaced on this engine was $700.00 plus but it ran flawlessly since 2009. That’s excellent performance for your dollar compared to poorly designed parts that keep failing over and again just when you don’t need it. The competition doesn’t have a chance against Cummins.