[QUOTE=robert98506;4461187]2005 Holiday Rambler "STOP" engine light on dash comes on and goes into limp mode.
Cummins engine ISC-330,
I took the coach to Cummins engine service center, they read the code and said the only reason "STOP" engine light on dash comes on is if you are low on coolant or the sensor unit is bad.
I changed the sensor unit and it cured the problem for a while, but then came back.
I changed the sensor unit twice, and after a couple months the problem comes back.
The sensor unit is a Ford part, XC4Z-10D968-AA
The sensor unit goes in the pressurized overflow unit of the radiator.
I can unplug the sensor unit, but then the Service Engine light on the dash comes on.
If anyone knows of a post that someone else has posted before, or how I can get to that post, let me know.
Thank you very much for your time.
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How long has it been since the coolant system was flushed and changed? A lot of problems can come from old worn out coolant.