HELP Acert wont start...

You swapped out the filter head between the tank and the pump? If thats the one that sensor is for the fuel restriction gauge. Sounds like you lost the prime either with a air leak in the line. Check your lines and the filter for air leaks. Take the hand primer and pull it up and put a little lite oil on it and prime the hell out of it, once it starts to get hard to pump it have someone crank the truck.

 

you probably have an air leak my buddy's t600 started having the same issues. They replaced 1 injector in Austin and was loosing power before he made it to Anna TX. He took the truck to Wisconsin Kenworth in Oak creek and the truck was good and had no problems even though it had low power . I got home went to the shop and I checked the truck tried a different fuel head changed filters and filled them to the brim and still the truck was emptying the filters. I took of pump and voila! a broken spring. Disassembled a pump off another Acert added another shim put back into truck and cranked it with a little help of starting fluid. My buddy's wife Called Wisconsin kenworth and told them about the broken spring they said it was impossible they had checked fuel pressure and when asked what the reading was their answer within specs WOW that is a good lie

 

this is what i would do remove 11/16 fitting on rhs on filter housing then reprime system.fass makes this real easy but i digress..good luck sir

 

If the hand primer didnt get harder after 1 or2 mins of pumping either you have a major air leak or the hand pump is bad and if the hand pump is bad air can be sucked in there. Also check the check valve on the bottom right side of the hand primer filter base, it can get weak causing a loss of prime.

Any time that I have to use the hand primer I use a small amount of lite oil to lube the pump seal.