High EGT, horrible mpg
 

I'm a new member to the site, but have researched issues with my truck through here before. I figured I was overdue to join.

Here's the deal: I'm moving from Alaska to Illinois towing a 37', 12.5K fifth wheel. Not the best circumstances to work through the kinks that inherently arise with a new combination, but that's what I'm stuck with. My most recent problem is that I'm getting high EGTs and horrible gas mileage. I'm running a TS performance six position chip reflashed with Swamps tunes to accommodate my 175/146 single shot injectors. The weirdness of it for me is that yesterday the same position on the chip worked great for the trailer/truck combination. I was easily cruising at 70-75 in overdrive and 1000-1050 EGT, 9-10 psi boost on level road. Today, I can't hold speed in overdrive even with 1150-1200 EGT. I was getting about 10 mpg yesterday, but 6 mpg today at 12 psi boost. As far as I can tell I wasn't dragging any brakes, my tires are fine, I'm not getting any hard starts or smoke, but the engine just doesn't seem to be developing the same power as yesterday. My two year old monkeyed with the chip switch and left it on the next higher setting after I shut down and restarted in hope that the ECU had just gone to an over boost "safe" mode or something. The next higher position acts pretty much like yesterday's performance. Any chance the chip or selector switch are casing this or am I looking at the front end of a downhill performance slide to an engine rebuild or some other horrendously expensive fix?

i would check for a boost leak first

What does that sound like? I've got some noise coming from the turbo that I thought was the notorious compressor stall/surge issue. It happens anywhere upward from 15 psi but mostly at lower engine rpm, high boost (i.e., trying to hold highway speed up a hill in overdrive, 15-16 psi). Could that be a boost leak happening instead? The induction tubes boots and intercooler are all stock, so I'm thinking some leaking is probably happening. Other than the gauges, are there visual indicators in the engine compartment to key on?:td:

some times you cant hear them, i would look over all the intercooler tubes and boots then check the uppipes.