My 2003 Ford F-250 6.0 diesel is fine when it is cold, but after it gets hot the engine hesitates and losses power. If I press down on the gas is runs fine for a minute. This mainly happens in the 1800-2300rpm range. I took it to a Ford dealer and they replaced the EGR valve and installed an injector pressure control sensor to the tune of $900. The problem appears to be getting worse. What is my next move?

Most problems with the 6.0 are caused by lack of maintenance, such as not performing regular oil changes. I would only use full-synthetic diesel HDEO in any turbo diesel. The two most common problems are with the injectors and the turbo--they have oil fired injectors. Therefore, not changing the oil as scheduled, or letting it get low, will cause problems by clogging the three “micro-screens” that are in each injectors. Dirty oil causes a build-up in the “veins” of the turbocharger, causing them to stick--then turbo issues really begin. These trucks are not “grocery getter” trucks for short trips-–they need to be opened up and run.

The link below may help:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-8.html#post1415281