no power, shakes when i drive, codes

[strickstroker]

i have a 99 f-250 7.3 185k and its the early 99 if that makes a difference.?

When i hook my truck up to a computer it pulls codes sayin a miss in the number 8 cylinder low turbo pressure, sumthin about the IDM , and a few others, I have been told that i need to replace the wiring harness in the valve cover cause it could have grounded out and can be making false codes. is this a common thing...??? this is my first powerstroke i need help

and the truck wont start in the cold even if i plug it in..

[Tyler]

You need to check your wiring but pulling the valve covers. If you don't know what to check for, take it to a buddy to help you out.
Have you chceked for gelled fuel? Where are you located, make sure your run anit-gel adds if your in the cold.

Do you know if your block heater it working? Plug it in overnight, and the next day pop your hood and put your hand on the valvle cover, or somehwere on the block. Should be pretty warm.

[strickstroker]

the truck has after market block heater the stock one is on there but dont work. it was like that when i got it. i did put the anti gel stuff in the fuel. but still no start. is it commmon for those wiring harnesses to go bad..?

[SCUFFY828]

remove the drivers side valve cover and youll probably find the harness to the injectors loose

[strickstroker]

do i need to replace the harness if thats the case..?? or just plug it back in.?