Turbo Howl??

[CMgill]

It's been cold here ( teens and twenties) and recently I noticed a sound from the engine compartment that sounds like my dogs howling at an ambulance siren. Engine temp has been less than full. Does not seem to happen at full temp. Occurs on gentle accel or no pedal decel between 20 and 25mph, peaks in loudness in the middle and can be maintained if speed maintained. Not flogging it and everything is stock 04. 5 600. Any ideas? Scared the crap out of me the first time.

 

[Prairie Dog]

Does the sound come and go with the grid heaters?

 

[CMgill]

Well, don't know that I could say. Didn't know what it was til you asked and I had to go look it up. How would I know that is occuring in association with grid heaters? Is this what causes the heavy power drain (amp gauge flux) and light fluctuations on startup. Any association with idle jump to approx. 1000 rpm when sitting?

 

[Prairie Dog]

I only ask because my old 93 used to make a high pitched noise like you describe whenever the heaters were on. You can usually tell they're on because the lights dim due to the huge current draw. The volt meter wont drop on an 03 because Dodge keeps it from moving while the heaters are on untill you hit 25 mph ~ keeps people from asking dealer whats going on.

As far as the idle jump, if it's cold enough, the idle will raise to 1000 after idling 2 minutes. Touching the brake or accelerator will cause the idle to return to normal.

 

[smitty3500]

My 04. 5 is making the same noise now that is is colder here also. I am not going to worry about it. That what warranty is for! Oo. The noise is only present when temp is below 25 it seems.

 

[420welder]

I have heard this same sound from mine since new only when it’s cold. Sounds like a ghost or blowing air across the top of a soda bottle or your dog. When the weather warms up it goes away. Here are a couple of links that talk about it



https://www.turbodieselregister.com/forums/showthread.php?t=88737



https://www.turbodieselregister.com/forums/showthread.php?t=152592



http://www.dieseltruckresource.com/dev/showthread.php?s=&threadid=35581

 

[CMgill]

Thanks everyone. Learned a few things with the replies (grid heaters and power flux's. Idle jump). Sounds like it is a "not uncommon" mystery of the Ghost in the Machine genre; lol. As with others in discussion threads the noise goes away when engine is up to full temp and I have never noticed it during warmer days or temps over 30 deg.

 

[RobertP]

mine has also been doing this for a while now but it seemed to start when i accidentally hit 50 plus pounds on the stock turbo. or maybe thats when i started to notice it more. who knows it still runs good so im not worried.



Robert

 

[Cattletrkr]

Mine makes some nasty noise on extreme cold starts... usually below 0* w/o being plugged in. Pretty much disappears once it warms up. Mine will immediately jump up to 1000rpm the instant it starts if it's cold enough, again probably below 0* w/o plugging in.



Sun morning it popped right off at -10*F no plug. Just let the heaters cycle once and away it went. Kinda scared me, I wasn't expecting it to go that easy. Fired and went to 1000rpm before I knew what was going on. Kinda nice.



So yeah, some loud freaky noises are normal.