2018 ENTEGRA CORNERSTONE Engine Problems

While driving across Florida, the “Check Engine” light and first of three DEF Head “Service Codes” on our 2018 Entegra Cornerstone 45’ RV came on, indicating that our Diesel Exhaust Fluid (DEF) system had an issue. From previous social media posts from other Entegra Owners, we immediately contacted the chassis manufacturer, Spartan. They requested that we contact Cummins-Orlando, FL for a DEF Head replacement. Cummins-Orlando said they couldn’t get us in for three weeks, which wasn’t an option, as we were traveling and couldn’t wait three weeks. We contacted Cummins-Tampa, FL and Cummins-Jacksonville, FL, with both stating 2-3 weeks to get us in. By this time, the second of three DEF codes came on, so the situation was getting more dire. We finally got through to Cummins-Ocala, FL and they were able to squeeze us in the next day. The third of three DEF Codes came on during the relatively...

Vehicle has approximately 30,800 miles. A check engine light with error codes SPN: 3364, 1761, 3331 indicating a failure of the DEF ( diesel exhaust fluid) sensor. This results in a degrade in performance to a point of engine shutdown. Replacement parts are very hard to obtain because this error is so common.

DEF sensor failed twice. Potential engine derate or shut down. Problem well known to chassis manufacturer. Failure announced by Check Engine Light and three well known codes. Time or distance to derate/shutdown is unknown, and consequently could result in a large motor home stopped on the road.

Shortly after starting the engine a “CHECK ENGINE” warning appeared on the warning system. I went through diagnostics and found 3 codes relating to DEF head failure. There have been a large number of these in Entegra Coach motor homes in the last 6-12 months.