Hey guys about a week ago my truck started running real bad, down on power a lot, and very shaky at any speed or at idle, I went to autozone to get the codes and i got the 3 above in the title, I had before 0171 and 0174 and the truck ran fine and now that i got these 3 codes it runs horrible, any ideas if they are connected? i havent done anythign to the truck in the time that they came up so i assume its gotta be something connected. I do know i have a hose that goes to the vaccum hub thats split but it has been split for a while. any ideas what the problem is? its a 98 4.0 thanks.

 

P0304-Cylinder 4 misfire
P0401-EGR Flow
P0455 - EVAP Control System Leak Detected
P0171 - System to Lean(Bank 1)
P0174 - System to Lean (Bank 2)
Here's some trouble shooting info
http://home.comcast.net/~miracerros/...wertrain_1.htm
It sounds to me like a major vacumn leak.

 

Do u think that that vaccum hose that goes to the hhub may have caused it? Any info on the evap system Idk anything about it.

 

i checked all the vaccum hoses in engine bay and cant find any leaks in those.

 

think that hose to the hub may have done it, as i read somewhere on here the egr is vaccum controlled, makes sense, i put hose on and it started running better, going on an hour trip so we will see here in a bit.

 

now all i have is a cylinder 4 misfire, after the plug what are the most likely suspects?

 

replaced the plug wires, seemed to run better overall but can still tell there is misfire.

 

did you change the plugs too? if thats not it could be a coil!
how many miles are on it?
if thats not it, could be out of time, cam sensor or crank sensor!