hi, have a 99' ram 2500mag v10 8 liter, 128,xxx miles. started having a "falling on its face' problem with it when accelerating, to the point at times it dosent even want to build up enough rpm to shift, took to shop and they replaced 8 of the 10 plugs ( the 8th one snapped off and had to be easy outted, said if other 2 break head had to come off and that would be an additional 600 in labor) did air filter and sprayed some stuff in throttle body to clean. truck seems to do ok at hwy speeds but getting there is the problem. this started about the same time it started having a bit of a hard start problem (engine turns quite a bit before starting), I was told by them the diagnostic machine will do no good as no check engine lights came on. Any ideas on where I can start as I dont want to pay shop 90 bucks an hour for the process of elimination, I dont mind paying but hate paying and it still dosent run better

 

Check fuel pressure first. If that's ok, check that you are getting spark on all ten cylinders. You have two separate coil packs there, each with it's own module. If one of the modules fail, you drop either 4 or 6 cylinders. That would be a major impact on performance. Might not be a bad idea just to pull both modules, and have them tested.

 

going to pull them and have tested this morning, thank you, will keep you posted.

 

Definitely test fuel pressure... it sounds like you are at the mileage where you will need a new fuel pump