Me and the truck had a bit of a hard weekend. This was my first towing weekend and the old truck wasn't super happy. I don't think anything is monumentally wrong, I just think I need to work with the tuner a bit.
When I am cruising while towing, I am seeing sustained IATs at 180F or so and EGTs around 1200F (in 90F outside temps). I think that is reasonable based on what I have read (and without running an intercooler). Also, the WB02 AFR was around ~14.7:1 when cruising with around 20-30 degrees of advance or so.
What I noted was that when I was off cruising speed (20-50%) acceleration, my EGTs would skyrocket up past 1400F on their way to 1500F+. During that time, I would basically lose all power and timing advance would pull down to single digits. IATs were around 180-190 max during this time. AFRs appeared to be around 14.7:1; that is to say that I didn't see the AFR change when I accelerated until I went WOT. I had two choices to correct this: I quickly backed off acceleration when I saw this or I had to downshift; then the truck would then get power back and EGTs would drop back down. When I went WOT or near WOT from a dead stop, I would see the EGTs climb high for a brief period but the truck seemed to have plenty of power until I reached cruising speed.
I did have one time when I was WOT pulling a hill at 65MPH, EGTs climbed very high (up to 1500F), and AFR was ~11.2:1;the truck pulled all timing and I heard very light popping sounds, like in an old hot rod when it hit the gas hard and then let off. I slowed down and downshifted and it was ok.
The truck is much more temperamental now. I basically can only cruise or go WOT in a lower gear. There is basically nothing in between and even under WOT I would see timing pull way back and it didn't have that much power at times. I feel like the truck may be on its way for a heart transplant if I don't get this figured out soon.
I have a suspicion that the knock sensor was picking up some knocks and retarding the hell out of the timing. I am only running 91 octane fuel, that is all I can get in CA. I am wondering if the tuner has me tuned for 93 octane and it was running too much advance. We'll see what the tuner says.
If we can't get a solution, I might have to take truck back to NA. I don't feel like grenading the motor on a family camping weekend.