ok , when i start it for the first time it shuts right off do that 2 or more times it'll stay running but barely, idles then chugs the whole way down, comes back up and down. keeps doin that and shuts off also, if i'm runnin down the road it does ok, lacks a little but acts normal til you let off then it chugs, hit the gas it seems ok again. have replaced the egr, would a crack in the head cause a vacuum leak or does it sound like something different? scratchin my head, need some direction. thanx

 

TPS most likely. Pull the error codes before you throw new parts at it...Could be lots of things.

 

what if the engine light isn't on, will it still show codes?

 

Have you tried cleaning your throttle body and MAF sensor? Mine was bogging down at stop lights but was fine while driving so I cleaned the TB and MAF and now she idles great and doesn't bog down anymore. My TB was almost completely cover on the inside

 

with just plain old carb cleaner or something special?

 

No!!! Use actual TB cleaner I used CRC tb cleaner and CRC MAF cleaner, carb cleaner will take off the coating inside the tb, there's a thread on how to or just google it but it only takes like 15-20 mins just don't touch the wires in the sensor. If you have a aftermarket cai, the oils make the tb dirtier faster. I used a toothbrush to clean mine and on the sensor just spray the wires 12-15 times and let air dry when you're done you have to drive it at least ten miles at different speeds so the computer can recalibrate your driving habits.

 

k thnx i will get some of that and try it. hope that's it

 

No prob, good luck!