Well wouldn't you know it, this morning it started fine! Around 30 degees here this morning. I'm not sure if that had anything to do with it. Maybe it had to reset itself after a few days? Anyway, I'm sure the problem won't just go away. I really need to know more about the IAC. All the post I've read seem to point to that. I've got 88,000 miles on my truck now and this is the first real trouble I've had with it besides the door locks.

 

IAC -

https://www.f150online.com/forums/sh...d.php?t=268137

 

I have had this same backfiring problem on my '04 FX4 w/260,000kms, and it has thrown the vacuum line at the bottom rear passenger side of the engine.
It happened after a pretty decent backfire with the smoke and the smell. (mind you the smoke came from the driver's side, could have been the wind, etc.) Both myself and my mechanic can't reach it from up top and to avoid removing the intake manifold we cut a little hole in the floor right at the pass. side of the transmission hump to be able to put the hose back on, but this time with some adhesive/tie strap, etc. So far the hole is about 4" x 4" in size and it couldn't quite be reached on a friday afternoon 5 o'clock, so first thing Monday morning he's going to cut it a little bigger and see if he can get at it. Has anybody ever heard of this method before? Wondering if it is actually going to work, otherwise my cab floor has been cut open for no reason...!

Mark
Pembroke, Ontario, Canada

 

Just an update on this topic. The idea worked perfectly. Other than the fact that the skinny arms of my mechanic's 12yr old son were required to reach the spot through the access hole and plug the hose back in, it was easy as pie!
Also put a plastic strap on the fitting so it will never come off again. Covered the hole back over with metal, rivets, and seam sealer and she's as good as new!

If this happens to anyone else, seriously consider cutting your floor before removing your intake. It saved me about $300, and who knows how long waiting for a back-ordered intake manifold gasket from Ford.

 

What and where is the vapor management valve?
I have exactely the same problem as you on my 04 3v 5,4, i could have written the post with the same words!
I think i do the same first!
Thank you in advance.

 

I now have tested the vapor valve, but it works fine.
Now i must check this hose behind the manifold.
Where does this go, and what is it for?
Anybody?
I am seriously concidering buying a Toyota instead of this crapy Ford.

 

I am having the exact problem with my 04 FX4. Have you figured this out? I would love to find a diagram that shows where this hose is located. Does anyone have any advise on where we could find this information. This is very frustrating!!!!!! Thanks in advance for any assistance.

 

Hi,

No, i still have no idle...
I checked the hose on the passengerside below the intake, but it is on....
However, i grounded the vapor management valve, and the idle was back.
Doing this i have to open the gas cap due to vacum in the tank.
I guess there is another valve who should open to let air into the tank.
Next thing is to check this valve.
Conclution is that the evap system is causing all the trouble.
Anyone who has experienced this???

 

I just bought a vapor management valve at the dealership for 55 bucks. I will put it on tonight and post my findings. Hopefully this will be the trick???

 

I cleaned mt throttle body & throttle plate(butterfly) & that fixed symptoms you are describing.

 

Well, I replaced the vapor control valve and thought that it was all fixed......then it started doing it again. It hasn't thrown another code yet, but once warmed up, it starts idling really rough and then will die. The hose on the top of the vmv that goes around the engine to the passenger side valve cover is really deteriorated and I am gonna pick up a new one tomorrow and see what that does. I am really frustrated with this thing. It seems that the exact thing has happened to a few people on here, but what fixes it for one doesn't do it for the next. Well, I will post what happens when I put on the new hose. If anyone has any additional info, it would be welcome!!!

 

My 07 250 4x4 was in last week for a similar situation. They said the MAF was dirty from water ingestion in the snow/slush. Whatever, as I already had cleaned it before I went to the dealership. They didn't charge me as I am still under the 36k warranty. Three days later, same thing but with a stall this time. Then the next day it stalls again. Nothing leading up to the stall like loading up or backfiring, just a stall. Turned out to be the electronic throttle body. Replaced under warranty and it's all good.

 

newbie to the forum here...i had my 05 5.4L motor die on me while driving to work today. i was going about 40mph when the engine cut out. After coasting to a stop. I was able to restart the motor and drive in to work without any further problems. The engine light is now on which sounds alot like the problems expressed in this thread. This is the first issue with my truck that I have had, well...other than a couple of window issues.

The good part is, I have 100K mile warranty. Ill be calling the dealer to get it in the shop asap. ill give a full report on what the issue is/was. Hopefully it will help troubleshoot some issues here.

 

Still no progress. I replaced the deteriorated hose for the vmv and it still idles VERY rough and WILL eventually die. I am now getting P2195 and P2197 codes, which means the O2 sensors are stuck in the lean position. When I reset the DTC's with my edge, they come back and also alternate with the banks 1 and 2 system lean codes. I am clueless and the dealership can't take my truck for 2 weeks. I sprayed carburetor cleaner all around my engine and all the vacuum hoses that I could see. The motor didn't seem to rev any like I have been told if there was a vacuum leak. Any ideas????

 

Just wanted to thank the ones that chimed in and gave advice on this subject. I ended up taking my truck to the dealership and they told me that it was probably the intake manifold gasket and would cost 600 bucks to replace it. I told them to check the vacuum hose mentioned here in this thread ( I couldn't reach it myself....). They called back and said that was the problem and fixed it for me. It cost about $250, but it is fixed regardless. I just wasn't real keen on cutting a hole in my floorboard, but I guess it would have saved me some money. Maybe this thread will help someone in the future with this strange problem.