Throwin codes and I don't know why.

[snow-junky]

I have a 99 7.3 that has been the best truck i have ever had.It's basically stock,it has a 4" exhaust,a diablo tuner(always set on 40hp),and a boost fooler.Thats it.

So my problems are that it sputters and throws the check light.The codes are p1249-wastegatecontrol valve performance and p1316-injector driver module codes detected.I'm no stranger to turning a wrench and not afraid to work on it , but I have no idea were to go from here.
I think an injector is going out , but i don't know how to tell.It wouldn't go into fast idle warm-up this morning either.


Any info would be greatly appreciated.

Thanks in advance

RYAN