ok got the 08 isx started but...

we replaced the lift pump, got it started ran for 480 miles better than a new truck when I got to my destination cut the truck off, got up in the morning started it, now it idles fast at all the time (1000RPM) no power up hills even empty. could it be the turbo?

 

the check engine light comes on for a period of time and other times no engine light. my throttle peddle sems to function ok when I step on it. 3 international dealers can't find any codes and they can't find what is wrong with the truck. when driving even empty in the 10th gear up hills I don't get any turbo boost ( my gauge doesn't read any boost) but if I down shift 1 gear to 9th gear the turbo start working and reading on my gauge the right boost and I have power then, if I have a load it seams like the 9th gear loose it is power after a very short period of time and then I down shift again and so on till i get up the hill, I maybe finish the hill at 5 mph where in the past b4 this problem I can go up hills with no problems at all @55-60 mph and loaded to the max. thank you for helping with your ideas, I need all the help right now to get back home and trade this thing in. so far is been costing me about $900-1500 a week trying to find the problem. thanks for your help heavy d.

 

how costly is it. just in case this is not the problem. thanks.