Been a great week fixing up the truck until...code

[Biggredd]

Been a great week/month of me fixing up the truck and feel like bragging a little. Just bought it a few months ago and thought I'd share what I've been doing to it, what it has and if I can easily fix this code.

Got a 08 F250 Quad cab, long bed 6.4 Already had a rhino bed liner, Amp auto steps and a Pioneer Navigation DVD head unit, 6" lift, 35" tires on some aftermarket chrome rims. I did get an upper radiator hose leak I had to get fixed and put some new batteries in it which sucked. But since then its bee good. Finished installing a rear view camera that turns on when I put it in reverse, got the auto start working on it, added a Spartan tuner with DPF and Cat delete with custom dash mount for the display, just got in the mail today my S&B CAI, got a 1 cubic foot box to go behind the passenger rear seat with a rockford 10" slimline sub (might need to do alot of trimming though to fit) along with a 600 watt MTX amp, got a trifold bed cover and a over the cab pop up style camper for summer. Been a good couple months.

I'm only running the 175 tune until I get the CAI installed and up the power. My question now is since I don't have that CAI to put the big tune with EGR turn off option I'm getting error code PO401. Will the EGR turn off alleviate this problem or is this the sign of a bigger problem spoiling my recent fun?