Stuck injectors?

Is it possible that all injectors are stuck after truck has been sitting for 5 years? Or could it be a ECM

 

My tragic story.....I have a 2004 WS Series 60 , (there should be a lemon act in Canada) after 3 motor jobs on this baby , and many hours of fighting with Detroit Engines, and the garage that did the work , Detroit relented and put in a new motor (thanks Detroit ) drove the truck home , pulled 1 load and bam truck down again! Went out and bought a 379 Pete so I could fund the WS! Parked the ws for 5 years and now they are telling me ALL the injectors are stuck, truck was parked right after the motor job. I know I had problems with the ECM wiring before the truck was parked , but garage is telling me its showing no codes for ecm. I just want some feed back from anyone that can offer,feeling very fusterated with this truck!

 

It wont start. New batteries, and fuel. Mechanic says it pushes fuel up to injectors but truck will not fire.

 

They say they had it on the computer and it is not throwing any code to indicate ecm, so they told me all injectors are stuck, took them a half hour to make this diagnoses. I do not know a lot about how this all works , but I feel being a female they will just about tell me anything cause I wouldn't know the difference.Just not too sure which direction I should go? Put the 5000 grand in that they said it would cost, or move it to another garage. Thanks

 

If that is the case do I have to replace them all with new or is there a way to clean the existing ones?