2002 Ford F250 W/7.3 bucking problems
 

Hello, I have 2002 Ford F250 with 183,000 Kms on it. I have a problem where when I am driving down the road trying to keep it at about 60 Kmph it seems to buck or grab and then let go. I took it to the shop and they said that #8 injector was bad so they replaced that. That did not correct the problem. Now they are telling me that the (ITC I think that is what they said ) comes up on the reader. This problem has been there for a long while and has recently gotten worse. I am from Canada and presently staying in Southern Texas. Can anyone shed a little light on the problem? The truck runs great other than a slight leak from the lines going to High pressure oil pump for the injection of fuel. Had the fuel filter replaced at PEP Boys about three weeks ago. Also replaced the head gaskets about two years ago because I was told that they were suspect in my oil leak. Turned out to be the "o" rings on the high pressure Pump lnes that go into the valve covers.
Thanks in advace for any help I may get.