High pitched whine when engine first started

[gcsb77]

I have 2010 F-450 6.4L with 2,030 miles on it. Had let it sit in the garage for about a week or maybe 10 days. When started, the engine sounded normal at idle but after warming for about 2-3 minutes followed by backing out of the garage and heading down the road, I noticed a high pitched whine associated with the engine speed. This noise was related only to engine RPM and not the transmission gear. Noise continued in 1st, 2nd, and 3rd gear. The RPM's never exceeded say around 1800 RPM. Again, at idle, there was no noise. This lasted only about 2 or 3 miles and then it stopped. Have not been able to repeat this event yet. This was the first and only time that this had happened. No codes or engine warning lights what so ever. Power was normal during this noise and no vibration occurred. Any ideas would be most appreciated.

thanks,
gbelk

[bucwheat]

Sounds like the valve that opens in the exhaust to warm the engine quicker,I have the noise but sounds more like a roar to me,it may also be your Turbo,louder when cold.

[gcsb77]

Originally Posted by bucwheat

Sounds like the valve that opens in the exhaust to warm the engine quicker,I have the noise but sounds more like a roar to me,it may also be your Turbo,louder when cold.

Yes, mine also was more like a roar. I could not even hear the normal diesel engine sounds. It was really weird in that as you pressed on the "go faster" pedal, the whine increased in volume , and if you pressed even farther (1500 rpm or so) it really got loud. I have never heard this sound before,,, even when the engine is cold. I have heard that you should not park these trucks for long periods of time.... things go wrong when you do.

Maybe, I should let the engine idle for 5 minutes or so before trying to move the truck ??????

I did not get any engine light nor did i get any sort of problem code....

thanks buckwheat,
gbelk

[gcsb77]

Originally Posted by bucwheat

Sounds like the valve that opens in the exhaust to warm the engine quicker,I have the noise but sounds more like a roar to me,it may also be your Turbo,louder when cold.

What is this valve called that opens the exaust to warm the engine quicker ??? How does it get it's signal to open ??

[HotRodDiesel]

What about a loose serpentine belt or something associated with that? Could be slipping

[gcsb77]

Originally Posted by HotRodDiesel

What about a loose serpentine belt or something associated with that? Could be slipping

this belt has been checked and not the problem. The truck only has 2,050 miles on it. Less than one month old.

[elibenson]

Originally Posted by bucwheat

Sounds like the valve that opens in the exhaust to warm the engine quicker,I have the noise but sounds more like a roar to me,it may also be your Turbo,louder when cold.

^^^ Sorry.. This is a 6.4l guys, they don't have "exhaust backpressure valves" They quit using those when they switched to the 6.0l.

Sounds to me like an idler pulley or something. They have been known to go out with few miles, There is even a TSB about idler pulleys.

[tucker]

My truck does the same thing. Only does it when I start it after it has been parked for a few days. I always thought it was the fan that was making all that noise.