I hope I have this in the right forum
I have a 2006 GMC SLT 2500 Duramax. 6.6 Diesel
I purchased it in January of 2012 with 89,000 miles
I now have 94,0000 miles on the truck.

The previous owner took VERY good care of the truck
He installed 4 inch Magna Flow exhaust. He did not install the Muffler. A straight section is welded there instead. I do have the Muffler, still in the plastic wrap. The previous owner also had an EDGE programmer in the truck but removed it before selling it. I wish he had not. It cost $800.00.

About 6 weeks after I bought the truck the check engine light came on. It stayed on for a couple days then went off. It did this a few times so I took it to the dealer. They read the codes and the Tech asked me if there was a chip in the truck? I said I didn't know. I still don't. He said the code was indicating something with the Turbocharger. But he didn't know what. He said it was probably minor and to not worry about it.
I paid $80.00 for that.

After that the Check Engine light would come on every couple weeks then go off.

Last week the Check Engine light came on and does not go off. I decided I could read the codes myself rather than pay the dealer 80 bucks again to have him ask me what was wrong with it.

So I bought an Actron Autoscanner. It works pretty good. Gives me the codes and possible causes and possible fixes. Starting with the most common.

The problem is I know nothing about Diesel engines so the codes are mostly a foreign language to me.

The codes I am seeing
P0101 Mass or volume air control circuit range
Replace EGR valve is the first fix listed

P2563 Turbocharger Boost control position sensor A
Possible fixes listed
Replace Turbocharger
Perform Turbocharger Learned procedure
Replace turbocharger vane position control sensor
Programm power train control module

P0674 Cylinder 4 glow plug
Replace Glow plug is first fix listed.


The P2563 is the one that has me worried. I would think a turbocharger for this truck would be very expensive.
The truck runs fine. Plenty of power and MPG is about 17. I do notice a little black smoke now and again at idle and there is a little soot at the exhaust after a few days.

My big question. Could this be the result of having the EDGE programmer installed and then removed and the 4" Magna Flow exhaust.
Also is there a place where I can get the information for reprogramming these systems or is that a dealer only item.

I hope I have explained this well enough and that I have this posted in the right place.
Thanks for any help I might get.