2015 · Peterbilt · 579 · Paccar MX-13

2015 Peterbilt 579 Paccar MX-13 - P0404 EGR Performance Issues

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1 Suggested
Issue / Concern

My MX-13 is acting up under load. When I'm pulling a grade, the truck starts surging and I see puffs of black smoke. It threw a P0404 code yesterday. I've noticed the coolant temp is creeping up a bit higher than usual too. I'm thinking the EGR valve is sticking, but I don't want to drop $1500 on a valve if it's just a sensor or a carbon buildup issue. Has anyone had luck cleaning these or is it a 'replace only' part on these Paccars?

Mileage
None indicated
Symptoms
None indicated
Tests Performed
Yes
System
None indicated
DTC Codes
P0404, SPN 2791
Keywords
None indicated
Already tried

Cleaned the MAP sensor and checked the CAC pipes for leaks.

DPF_Doc55· 215d ago
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  • GrandmaGeartooth64· 250d ago
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  • ShopBossMike87· 254d ago
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