I was told a while back that I had a leaky "Y" pipe when I took the Truck In for recall. This morning I walked out to my truck after letting it warm up for about 8 mins and I could hear this loud PSSSSSSSSSSSSS over the sound of the motor at the 1200 high idle. I lifted the hood and felt around by the thing right in front of the turbo that stands up that the intercooler pipes go into(i dont know what part that is called) and i couldn't feel any air blowing or sucking but it is really oily and dirty down in there. any ideas what it could be? I was thinking maybe one of the seals at the bottom of the previously described part ( like the intercooler seals) down in the valley of the motor? I have no idea what to call the parts i am looking at so that makes it hard to search the forums. thanks for the help!

PS.. when I got home from the coffee shop the sound was too quiet to hear over the motor. and the truck was warmed up. what the heck dude?

 

I might be the red hose/s leaking below your Y pipe .... see the following link for pictures.. look at steps 14 & 15.. in the link..

https://www.ford-trucks.com/article/...tallation.html

 

Are you sure it wasn't the wastegate closing to enable engine warmup?

 

Sounds normal, was it cold outside? The EBPV? closes and shuts off the exhaust and gives the engine back presure as well as adds rpm to heat the engine up. Hope I said that right.

 

That thing is the y-pipe or intercooler spider.



Inter cooler pipes



There is six IC boots, two at the bottom of the spider and one on each end of the pipes which are prone to leak. Clean up real good to see if one of them is the culprit. The oil in the pipes is normal. Are you low on boost

 

Holy freakin' SHINY IC tubes Brian!

 

When you had the stock exhaust, the same thing happend, but now that you have the 4" you can really hear it. You will also here this under light load ( while driving) conditions.

 

Actually I don't think the EBPV causes the engine to go into high idle. I have mine disconnected because it started closing on me while I was driving. The PCM still raises the idle when cold and everything works the same minus the EBPV function.

Just for clarification. Since they generally happen during the same time, one might think that the high idle is the result of the EBPV closing. This is not the case.

 

Brian, are those chromed or just polished?
Very sharp!

 

So this is normal for it to close while under light load? Mine started doing this and it was very annoying. It opened back up once I pressed the pedal down enough but it was not a very smooth transition at all. The engine was completely warmed up so I figured it was a problem with it coming on and getting in the way. I did remove my AIH though and it was about 15* when it did it. [/hijack]

The hissing sounds normal though. Unless you can actually find the leak, I would suspect that it is the normal EBVP operation. Mine sounds like a jet engine...seriously.

 

Chromed bruva

 

Yes, very normal. And I am guessing that you were not completely to temp, at least that is my case. When I look at the gage, I am convinced that I am there, but a couple of minutes later it gets a tad warmer and the hissing no longer happens.

I have ran with out the the back presure valve, and didnt see a difference in warm up time, so if you wish to unplug it just to be sure, it will not hurt anything.

 

I currently have it unplugged. I may plug it back in and drive it longer to see if it goes away. I see how the PCM could possibly want it to come into play during those conditions. It was very annoying though. It was the first time it ever did it. I was on the interstate running 70 when it started so I thought it was a problem. haha.

 

The hissing is the EBPV, and yes its normal for it to shut while driving if the engine isn't fully up to temp, which is why many of us have them unplugged. I'm going to be wiring mine to a switch here soon I hope so that I can shut it when I'm warming up the truck, and turn it off to drive and not have to deal with it cycling while driving.

 

Ok thanks for the advice, the jet engine sound comes from the tail pipe not under the hood, so its not that and it was just kind of convenient that i had seen a mod for the boots under the y pipe (aluminum inserts) that way you can crank down the boots tighter. Also the dealership had just told me that the y pipe was leaking (same area). I don't have any idea what my boost is, i don't have that guage. what is the normal amount of boost?

dude, those intercooler pipes are kick *** lookin!