Hey guys,
I just changed the engine in an 04' F350 6.8L, got it all together, EXCEPT i seem to be missing the small coolant hose that connects to the PCV valve on the plastic plenum on top of the intake manifold. there are two small coolant hoses that go to the valve, the one that comes off the front of the intake manifold (where the heater hose also connects to the intake manifold) is present and in place, but the hose that comes off the top of the valve and points towards the drivers seat, i seem to be missing! can not find it anywhere, NOR can i seem to find where it is supposed to go on the other end, which is why im posting! obviously i can replace the hose with another one, but where does it go to??? it comes off the PCV valve, and goes WHERE??? please help!

side note (maybe?) truck started up fine, but is running with a bad misfire (seems to be multiple cylinder, cause if i pull a coil connector on any coil, it does not seem to make much a difference) does anybody think this missing coolant hose could be my problem? or, will these trucks misfire if there is no coolant? still havent bled it fully yet (i know on hondas, if there is no coolant, they will idle funny cause of the IAC)

let me know your thoughts!
thanks guys!

 

Any body got one they can look at for me??

 

I'm guessing the pcv system changed in 04 because I looked at the system on my 03 and there are no coolant lines involved in the system. My 4.6 has a coolant heated pcv system, which might be similar to your system. Are you able to post pics of what you are refereeing to?

 

Mines heated but it’s electrically heated (California emissions truck) no coolant lines going to it and then there is a non heated version (federal emissions trucks) I wasn’t aware of any other type of pcv system for the v10. The pcv valve is on the passenger side valve cover so I don’t think your talking about the pcv valve and it sounds like your missing vacuum lines not coolant lines with the rough running and no change by disconcerting coils. I’m with ford merc I think we need a picture of what your looking at. Pcv is the same in 04 as it was in 03.

 

i am missing this top port. yes you are correct, the valve itself is on the valve cover, but this is where the pcv hose connects to the manifold (big hose to the left, green tab). the port to the bottom is a coolant hose and i have it hooked up already. when i cover that missing port with my finger, it has no vacuum to it.



the bottom port hose connects here, at the front of the manifold, right where the heater hose connects to the manifold. AllData says that they are both heated coolant hoses, also.

I will not through out the idea that I am missing a vacuum hose somewhere else, but it is not hissing like a vacuum line, and i cant find ANY other open port anywhere lol.

 

well i found where it is supposed to go, the pipe that comes out of the back of the water pump and goes through the valley and up the rear passenger side cylinder head, before the rubber hose connects it has a small nipple sticking out. HOWEVER, the engine i got does NOT have that nipple on the pipe! and the intake plenum (which i did not swap over) is different, so the truck this came out of must not have had the same pcv set up. possibly out of a different year. as long as all of that stuff is swapped correctly, and everything is plugged in, no missing connectors or anything, the fact that it came out of a different year should not be the reason it is not running great, right? or is there something drastically different from year to year on these trucks?

 

What year model truck is the replacement engine?

 

oops, i guess i forgot to mention that information. my replacement came out of an 02' 350 super duty. and the pcv area on the plastic plenum on top looks way different, but thats about all i can tell. I swapped over the whole intake manifold/plastic plenum, injectors and rails from the old engine (just missed that one steel coolant pipe that was different, didnt swap that and that is why i had that missing hose problem) all connectors have matched up, no stray harness connectors, no sensors without a connector. anything else that i could be missing, or should everything else pretty much be the same besides that pcv stuff?

 

I believe this is the line that you are referring to from the water pump to the backside of the motor.





Here was my issue https://www.ford-trucks.com/forums/1...turn-tube.html

 

yes. that much i already figured out. just finished swapping that. now just wondering if there is anything else, besides the pcv set up, from 02' to 04', that is drastically different that could cause the engine to run, but not well. it has not thrown a code yet, which is frustrating. so just wondering if there is anything else that should be changed or swapped before i start going crazy trying to diagnose this issue.