I've been having a CEL for P0401 coming on since I bought this truck in 2018. 03' f250 w/ 6.0 @ 147,XXX miles. CALIFORNIA truck. NOT deleted. SHould theoretically pass minus the CEL for P0401. The truck runs great now. No major known issues currently. I've replaced EGR valve, bulletproof EGR...

Just had the check engine light come on. Checked with my scanner p0401 exhaust gas recirculation flow insufficient detected. Truck has no noticible driveability issues. No leaks or coolant usage. Just noticed more frequent regens in the past few months. Truck has 32500 miles, 1313 engine hours...

*New Power stroke Owner* Just purchased a used 2011 F250 Lariat with the FX4 package, 110,000 miles this past Saturday. On Monday the CEL came on throwing 3 P0401 codes "exhaust gas recirculation flow insufficient detected." The truck seems to be running fine, all gauges are normal. I've got a...