Kenworth T680 PACCAR MX-13 Repeated Regen Failure and Derate

Question

My 2016 T680 keeps kicking out of a parked regen after about 10 minutes and now I'm stuck in a 5 MPH derate. I can hear the exhaust note change like it's trying to get hot, but the soot level doesn't drop on the dash.

Megan Rivera · Accepted Answer

The issue was a completely plugged Hydrocarbon (HC) Doser valve (Part #2133312PE). I removed the doser and found the tip was caked in hard carbon. After replacing the doser valve and the fuel line gasket, I forced a service regen using DAVIE 4. The exhaust temps finally hit 1100F, the soot level dropped to 0%, and the derate cleared. Total cost was about $450 for the part and two hours of labor.

Rachel Nguyen · Answer

Check your 7th injector (hydrocarbon doser) on the turbo outlet. If it's clogged with carbon, it won't spray enough fuel to maintain the exhaust temperatures required for a full regen cycle.

Marcus Bell · Answer

Run a relative compression test via DAVIE software. If you have a weak cylinder, it will put out too much soot for the regen to handle and it will time out before the soot level reaches the target.

Sam Holloway · Answer

Look at your Delta P sensor tubes. Sometimes they get pinholes or condensation frozen inside which gives the ECU a false pressure reading, causing it to abort for safety.

Kenworth T680 PACCAR MX-13 Repeated Regen Failure and Derate

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