Couple weeks ago, pulling 5000# trailer, traffic was slowed down to 35 or so then opens up on big hill, I shift to 4th, floor it, then 5th and I'm going WOT about 2700 rpm and I hear a ding. Gauge check shows I'm over heating, I back off and temp drops right away. Get home, find that not only is air filter dirty but something built a nest in the filter box. Fix all that thinking airflow was my problem.
Same trip this weekend and still does the same thing, closer to home I dropped it into 5th and floored it, it heated up, but also seems under powered at higher rpm's.
Thinking maybe the cat is plugged up, truck drives normal, runs good until I rev it up.
Can I check the cat without removing it?
2006 megacab, 5.9, 6spd manual. New water pump last year

 

have you checked the turbo to see if maybe it sucked up some of the nest

 

Easy enough to check just disconnect and go drive truck. How's the fuel filter? Low fuel pressure could cause lack of power also.

 

Will start checking on some things this afternoon hopefully. Thanks for tips.

 

I would also check pressure limiting valve, if you have a way to monitor the fuel pressure at the rail. Set point pressure and actual fuel pressure should be the same. If set point is 29,000 PSI and actual is 9,000 psi then I would be looking at the limiting valve for leakage.