Weird Noise When Cold

[MNDIZZLE]

2003 F250 7.3. I live in MN.
When it's cold out and I let it idle for a while to warm up, the engine occasionally makes a wicked "whooshing" sound, then it goes away, then comes back, then it wheeses and whistles a little. It sounds like a jet engine at the exhaust. Kinda cool, but is it normal? It scares the hell out of passer-by's. Goes away when the oil temp gets to about 130*. ???

[cblackb]

Well, there is a flap that closes just behind the turbo in the exaust pipe...it closes when it's cold to assist in warm-up. This is most likely what you are hearing. It CAN be loud sometimes, mine is too the colder it gets outside.

[sea71]

Your exhaust back pressur valve will close when its cold out to help the engine warm faster. When it starts to open a little is when you will here that loud whistling(jet) sound. I am confused about the whoosh and the sound coming and going at hiway speeds. My Guess is that it is opening and closing for some reason. Never heard one do that that I know of. Someone with more knowledge will be along shortly to help.I dont know what makes the valve open and close so I would only be guessing at that point.

[djsdiesel]

It's your Exhaust back pressure valve closing to aid in warm up. It is normal for it to come on at steeding cruising speeds also. You can unhook it. It will set a code in the computer but it won't turn on the check engine light. If ou look below the turbo on the turbo pedistal in the front their is a two wire plug, unplug it. this will disable it from actuating. Mines been unhooked for 2 winters now (1-winter unplugged 1-winter completly removed valve fom housing) and have not noticed any difference in warm up time.

[MNDIZZLE]

Good to know. Thanks guys!

[slpin]

mine did it today when i started my truck and went driving

it seems to turn off after certain throttle position, the truck was already above the line for normal operating temperature...

it was snowing.

[MNDIZZLE]

Originally Posted by djsdiesel

It's your Exhaust back pressure valve closing to aid in warm up. It is normal for it to come on at steeding cruising speeds also. You can unhook it. It will set a code in the computer but it won't turn on the check engine light. If ou look below the turbo on the turbo pedistal in the front their is a two wire plug, unplug it. this will disable it from actuating. Mines been unhooked for 2 winters now (1-winter unplugged 1-winter completly removed valve fom housing) and have not noticed any difference in warm up time.

O.K., I just tried that. I'm guessing you're talking about the only 2-wire plug that I see. Right in front of the Turbo Plenum, before it splits off into the intake?
I unplugged it, and got an "1119" trouble code. No light, just like you described. But I fired the engine up and the valve still engages. Whoooooosh! ???
Wrong plug?

[djsdiesel]

wrong plug, it's behind the y-pipe, on the turbo pedistal. heres a pic of the turbo. its the plug towards the bottom of the pic in the middle, right above the blue circle. P1119 is the manifold air temp sensor. You should get a p0475, or p0476 with the EBV wire disconnected

[MNDIZZLE]

Thanks! I'll try that.

[MNDIZZLE]

NICE!!!