Ok so i dont think the 2 issues are related but about a month or so ago my 05 6.0l with 166000 miles start making a loud whistle sound when i touched the throttle or at high idle. Ive just been dealn with the sound bcuz i had some unexpected bills come up, but now when its cold or even just chilly outside when i start it theres a nice amount of white smoke for about 3-5 seconds then it quits(this kinda lets me see alittle bit of smoke comn from the front of the truck im thinkn this might have somethin to do with the whistle sound). So now it has a nasty miss to it im thinkn its a bad injector so is there a cheap way to check the injector because the dealership whats $200 to run their test? Any insight on these issues would be appreciated. By the way all injectors are stock except 1 got replaced last year about the same time.

 

The past 2 times that its been a loud whistle and white smoke at start for me has been the y pipe. They crack at the flex bellows on the passenger side. When you truck is cool start it and stick your hand to the left side of the turbo and feel for air rushing out. You will be able to tell right away. Don't get a new one from Ford it will break again. I just got the HD one from Rudys Diesel for $299 stainless braided flex bellows.

 

Other than leaking exhaust fumes under the hood and into the cab, what other issues with a cracked Y pipe cause? Decrease in performance or mpg? I am starting to wonder if mine is cracked. I am getting exhaust smell int he cab when sitting at a light or parking lot, I am getting whistle, more like a hoot owl, when I let of the throttle. All ready replaced the degas cap. And my mpg has dropped considerably. Yes I have taken winter fuel consideration but it has dropped more than it did last year and dropped when the whistle started.

 

Thanks i will check that out after i get home from deer huntn, and i do get a faint exhaust smell n the cab aswell, how much much stuff am i gonna have to take apart to get that y pipe off or is it accessable without removing a bunch of ****, of course it has to happen when its getn cold in ohio ran like a raped ape all summer now gotta fix that and im pretty sure an injector is goin out to. Zejokee ive got a loss of power almost like a miss but im putn that off on the injector so kinda hard to tell u if thats causing my problems or if its the injector.

 

Loss of power since you will be loosing boost, exhaust smell in cab, decrease in mpg. Sometimes it will run rough. You will have to pull the turbo to get the the y pipe. I went ahead and did the hd y pipe and replaced the up pipe to a solid one.

 

What if you are still getting proper boost? And the truck still has power and will scream if I stomp it.

 

Really would depend on the size of the crack I would guess. Smaller crack would be a louder pitch whistle while still keeping some what the correct boost level. Bigger you get the quitter it gets. But if your smelling exhaust in the cab from the vents im guessing its the y pipe.

 

Ok so i got home from work and felt around while puting a coolant jug on the throttle pedal to make the noise i could feel a small amount of air coming from the y pipe. But as i was looking i found a black wire with an elongated plug on it that is disconnected im not sure if its supposed to b or not but i really doubt it. Its on the passenger side of firewall kinda behind the ac i took a pic but no clue how to post it on here i could send it to someones email or phone if u let me know thanks