P245a/245c after EGR and cooler cleaning

[08_2500]

So I had a P245C before but when i bought the truck the EGR service was due, I finally got around to cleaning it this weekend. But now i have a 245a and c when i clear the codes with a basic reader the 245c comes right back,

I also had a P4 something related to egr but I test drove it once up to temp and turns out I have a few leaking gaskets afterwards. I have tightened all up for the most part but have to chase one more in the morning.

when i was cleaning the bypass valve was pretty rough as well as the egr valve, both are moving like butter now and i can watch the bypass valve move when it is warming up.

I am guessing i have an earlier 2008 there was an extra large square gasket in the geno's pack that i have no idea were it goes and the coolant connections have rubber hoses and band clamps, the right side of the egr pipe does not take a gasket it is machined with a lip.

Any idea how to clear the codes? pr what needs don to repair the truck?
Thanks 08 2500 6.7 auto 4wd

 

[RVTRKN]

The large rectangle gasket is for the Air Horn, the EGR is bolted to. I removed mine and cleaned the horn as well as the heater grid, then tapped for my boost, instead of the boost bolt.

 

[Bob4x4]

p245c

Possible Causes

(K670) EGR COOLER BYPASS VALVE SIGNAL CIRCUIT OPEN/HIGH RESISTANCE
(K670) EGR COOLER BYPASS VALVE SIGNAL CIRCUIT SHORTED TO VOLTAGE
EGR COOLER BYPASS VALVE
ENGINE CONTROL MODULE (ECM)