Vacuum leak

[Nick Falcone]

I have a vacuum leak throwing a po446 code. I found a location of the leak. Can anyone identify if this hard plastic broke off or if it was just a dry rotted rubber hose here ? Also what this vacuum hose is for I tried tracing it back . Thanks !

 

[Nick Falcone]

Forgot to mention it’s a 5.4L

 

[Plati]

that looks the one …. on my 2003 … that went and air only blew out the defrost
seems easy enough to fix. just get some hose that fits both sides and bridge, or just use Gorilla tape.

 

[Nick Falcone]

Air is only blowing out my defroster as well.

 

[Nick Falcone]

So that was an easy fix. Piece of rubber hose and now my vent blow again instead of just my defroster. Now I just have to figure out why it’s misfiring still

 

[Plati]

So that was an easy fix. Piece of rubber hose and now my vent blow again instead of just my defroster. Now I just have to figure out why it’s misfiring still

have you ever looked at the rubber elbow coming off the PCV valve?
they crumble

not that that has anything to do with 446

 

[Nick Falcone]

This is the only code coming up . (Ty by the way for the info on the vacuum leak)

 

[Hamfisted]

For the P0446 code you need to check the condition of the wiring harness/plug and the actually functionality of the evap vacuum control valve back there above the spare tire. Lower the spare to get to it. Sometimes that control valve just wears out. Other times it's the ground wire in the harness lead itself. Any little crack in the insulation of the wiring will allow corrosion to set in and disturb the current flow to the control valve.
Here's a good video describing the trouble shooting of the valve.

 

[Nick Falcone]

Would this cause my vehicle to misfire ? I’m noticing the truck is bucking at lower rpms while driving . I’m not coming up with any codes for cylinder misfires though.

 

[TobyU]

Just hook it back together with a piece or rubber tubing.
Then your hvac direction will function. Most ford trucks have a hose in this area that goes into the dash to control the flaps inside etc.

It's a pretty good vacuum leak so it will cause dip in idle and what can feel like a miss at low rpms. Get it hooked back up, clear codes and see it any pop up or you feel any misses.

 

[BlackCoffee]

I did the same repair last year after a rebuild. Just used a little silicon hose.

 

[BlackCoffee]

Check the lines and the EVAP valve next to the brake booster. I replaced that recently. Didn't buy the expensive Ford lines, just used silicone lines and clips. Two different size lines. It is actuated by vacuum (the small line) which could give a misfire. Also, the one line in the EVAP routing goes to the upper intake manifold behind the throttle body. You could have a leak in the vacuum system there. Here is a picture before repair. Replacing my valve solved my 446 code, but I also replaced the lines.

 

[Jdcline54]

That could definatly cause what you describe.
Although it might not be the problem. The only way to know is to fix the issue causing the p0446

 

[Msport]

I also had to replace the yellow line off of the evap valve next to the brake booster (blackcoffee's pic), I don't remember the code I got, but the line was burnt and causing the code.

 

[Nick Falcone]

Hey everyone just an update because I forgot to do it when I fixed this issue. It was the EVAP control valve where the spare tire is. It went bad. 60 dollar fix. My misfire was another issue 2 coils went bad cylinder 2 and 3 also the last person who did the coils snapped the screws into the plenum on cylinder 6 and 7 so the coils vibrated up. Had to tap them out. Thank you for all your help!

 

[Nick Falcone]

For the P0446 code you need to check the condition of the wiring harness/plug and the actually functionality of the evap vacuum control valve back there above the spare tire. Lower the spare to get to it. Sometimes that control valve just wears out. Other times it's the ground wire in the harness lead itself. Any little crack in the insulation of the wiring will allow corrosion to set in and disturb the current flow to the control valve.
Here's a good video describing the trouble shooting of the valve.

You were 100 percent right thanks for the help!!