Hey guys i have a 2004 dakota 4.7l, i did a recent engine swap (1000 miles ago) with a re manufactured engine. the truck since around 800 miles ago has developed a rough idle which at first cleared up once the truck reached running temperature but now pretty much stays rough when truck is parked and then truck is not moving pretty much at all times. i replaced the tps sensor, im going to try the idle air control valve today. this motor swap was my first one and although everything went smooth could i have left something out or did something wrong to cause this? also at highway speeds when i get on the the gas it almost feels like the truck is "spooling up" like unless i really get on it the throttle response is only ok. i have a scanner tool but i dont know enough about what im looking at to understand if there is a problem being displayed. there is no check engine light and the engine has not overheated once since i installed it. im at a total loss and i have dumped a ton of money into this truck so far and i could really use lots of suggestions. thanks in advance guys!

 

since it sounds temp related I'd go with Map sensor,

 

ill give it a try, the problem at first seemed to be more related to temp but in the last few weeks it hasnt seemed to get better even with it at running temperature, do you still think its the map sensor? is there a way to test it before i buy one?

 

since my problem is now pretty much constant at idle pace do you think it could be the fuel filter? is there any way to test the fuel filter?

 

No way to test a fuel filter, but there are pretty darn cheap....