Mystery vacuum line

[Trav125]

Good day to all!! I was recently driving and all of a sudden my truck got loud and started shaking and a check engine light came on. I scanned it and got a p0306 and p0304(misfires) so I go under the hood I immediately see a broken vacuum line behind the battery box. Fix that, sill have a problem. So I go full tune up - new coil pack, wires, and spark plugs. Still loud and shakey. Gives me a new code for the idle air control valve, in my case there is not a iacv, its a drive by wire... so I remove the throttle body, cleaned it better than a hooker before church. Checked and cleaned the egr valve. Still shaking!!!!! So now on the passenger side towards the back of the motor notice a hose, not connected to anything, and i can't find where this hose goes, but its coming from what looks like off the top of the tranny, I know the tranny does not have a vacuum line but where does it go?

 

[Trav125]

Good day to all!! I was recently driving and all of a sudden my truck got loud and started shaking and a check engine light came on. I scanned it and got a p0306 and p0304(misfires) so I go under the hood I immediately see a broken vacuum line behind the battery box. Fix that, sill have a problem. So I go full tune up - new coil pack, wires, and spark plugs. Still loud and shakey. Gives me a new code for the idle air control valve, in my case there is not a iacv, its a drive by wire... so I remove the throttle body, cleaned it better than a hooker before church. Checked and cleaned the egr valve. Still shaking!!!!! So now on the passenger side towards the back of the motor notice a hose, not connected to anything, and i can't find where this hose goes, but its coming from what looks like off the top of the tranny, I know the tranny does not have a vacuum line but where does it go?

 

[plasticseng]

It's probably the vent for the transmission. It won't be hooked to anything.

 

[Gmctyphoon]

Yup that’s a tranny vent hose. It just sits there.

Sounds like your problem could be wiring to the injectors. I’ve seen the insulation for the wires corrode and make the injectors not work. Try unplugging and plugging in the injectors and moving the wires around. If it makes a difference then check the wires.