I have a 7.3 PSD in my 00 Exc. I pulled a 1500 lbs trailer 200 miles about three weeks ago, and it was fine. Now it hesitates on acceleration,mostly when first started(AM or PM) *I am about 400 miles over on my oil change. Could that be the cause? I did plug it in to see if it made any difference in the AM- did not! Any ideas would be helpful!

 

Are you running a tuner of any kind? Do you have a way to check your fuel pressure? Could be an IPR issue. You could try cleaning it or swapping with a known good one.