I don't buy that. Fuel makes exhaust temp not air. They go to the expense of putting a air to air heat exchanger on the front to cool the air heated by the compression of the turbo ( the rule of thumb is every degree that you can cool the intake air you will cool the exhaust by three degrees).
Cool dense air makes horsepower not exhaust temp.
Jim O

 

then we should be putting smaller turbos on our trucks to cool EGTs

 

I want to argue with someone. ohh n/m That is true to a certain point I think but not always the case? After I saw this thread the other day I started watching my eg'ts to see if they went up when it was in the mid to high 20* range and on up. my observations showed that if it did increase egt's it was nominal but that my boost went up 4/10's of a pound according to my bd x-monitor my egt's haven't been able to hit 1300 when the ambient air temps are below the mid 50's. Unfortunately I didn't have my guages yet last year when I was in Iowa in januaryand for a week it never got over -6. If I had I could have proven one way or another, but there are plenty of guys who live in cold climates that could chime in on this one.

 

"The reason that doesn't show a code is because the TST box is sitting between the rail sensor and the ECM and its feeding the ECM the correct pressure ! Geesh !"

No need to get testy I will again respectfully disagree. The TST box doesn't do anything to the rail sensor. You must be thinking about some of the pressure boxes. This is why I choose the TST box as the example and not any of the boxes that fool the pressure sensor.

"If your filter was really plugged, the duty cycle to the fuel actuator would have been 100% and your rail pressure would have dropped. That would set a code. If you want to check this, just pull the fuse for your fuel pump and let the engine starve a bit. "

I never said the filter was completely plugged. Your test above would simulate a near completely plugged filter, as the lift pump is designed to be shut when it's not running to keep fuel from draining back to the tank. This would not be a similar test.

The conditions I listed had the truck able to idle fine, but when higher power conditions were being attempted (going up a hill, etc.) the demand for fuel was more than could be sucked through the filter. This happened multiple times to me without ever setting a code, and each time taking care of the fuel filter fixed the problem. I also believe if you go through the archive here you will find numerous examples of changing the fuel filter helping with fuel starvation problems and rarely was there any codes set indicating a problem with the filter.

 

This thread has an example of what Superduty and I are debating:
https://www.dieseltruckresource.com/...ad.php?t=82692

"1 mile from my house ,truck died would run for a minute ,then die. I had the truck at dealer last week for a bunch of maintenence things and told them to look into the pump because it was acting the way youse guys said it would before a failure. They said no codes so no new pump.Well now they have no choice. Then the tow truck never came ,so i walked home and found the code was for the lift pump. 38000 miles on the odometer.From what i have read they should be doing the in tank pump,am i right?
"

In it you will notice that the truck only set a code in the most severe case of fuel restriction (truck died), but when the guy was starting to notice issues related to fuel restriction the truck had not yet set a code. This is another example of why I'm inclined to believe there is a more complex relationship than the simple description Superduty has offered.