2004 2500 going under load when put into drive
 

Hello this is my first time posting on here. I am working on a 2004 Dodge Ram 2500 4wd with a 5.9L diesel and automatic transmission. The complaint is that when the truck is put in either reverse or drive the truck drops from idle at 700 rpm to 500 rpm and spools up the turbo and builds back up to 700 rpm. You can then put your foot on the throttle and do WOT and there is no response. It just sits there idling at 700rpm spooling up the turbo. No check engine codes have popped.

what do you mean" spooling up the turbo"?

what do you mean "spooling up the turbo"?

what I mean by spooling up the turbo is as it is sitting there in drive or reverse gear at 700rpm the turbo is turning like it is under load at higher rpm. It sounds like the turbo is turning at a high rpm as if the engine was under WOT, when it is only sitting at 700rpm but the engine seems to be under a load too.

First thing i would look for is voltage to apps or throttle position, as you move the pedal it should go up from 0.00 to 4.99 volts i believe. Then check readings on all other sensors. Key on engine off none should be at the high range. Like 4.90 or higher. Sounds to me you have an incorrect or misreading sensor. Which affects all of them being on the 5v reference sometimes. If you don't have a scan tool, Start by unplugging the cooling fan. Under the radiator, this seems to be the most common one to confuse the others and cause no starts.