Kenworth T680 PACCAR MX-13 Forced Regen Won't Complete - Low Exhaust Temp

Question

I am having a hell of a time getting my 2017 T680 to finish a parked regen. It starts the process and stays at high idle for about 10 minutes, but then it just kicks out and gives me a 'Regen Interrupted' message on the dash without a specific fault code. It's currently in a 5 MPH derate and I can't move it until this clears.

Jordan Lee · Accepted Answer

The issue turned out to be a failed 7th injector (Hydrocarbon Doser). The tip was completely blocked with carbon, preventing fuel from atomizing into the exhaust. I replaced the doser valve (Part #2140766), performed a forced regen via software, and it completed successfully. My DOC inlet temps finally shot up over 600 degrees as they should.

Chris Donovan · Answer

You need to hook up DAVIE or a diagnostic tool and watch the DOC Inlet and Outlet temperatures. If the inlet is hot but the outlet isn't rising, your DOC is likely face-plugged or the fuel isn't reaching it.

Rachel Nguyen · Answer

Check your coolant temperature while you are attempting the regen. If the engine isn't reaching at least 150-160 degrees, the ECM will often kick the regen out for safety or because it thinks the thermostats are stuck open.

Greg Walters · Answer

Have you looked at the doser valve (hydrocarbon injector)? If the nozzle is carboned up, it can't spray enough fuel into the exhaust stream to get the DOC hot enough to burn the soot out of the DPF.

Kenworth T680 PACCAR MX-13 Forced Regen Won't Complete - Low Exhaust Temp

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