Hard to describe.... Trumpeting sound? - UPDATE

[gmoney]

Hey everyone,

Hope you guys are all doing well. Here's the latest: I've noticed that when I accelerate, I hear this "trumpeting" sound... I know, I know it sounds odd. But that's the best way I can describe it. I've only mostly notice it when the car is still cold, but there are times when I've made sure it's warm, and I still hear it when I hit the gas.

And I'm not really punching it... just accelerating normally. The sound fades away as the engine's revs drop... in other words, the trumpeting sound starts, rises and then goes away as I accelerate and then the RPM's drop. Then, after a while of driving it seems to stop altogether.... it's gone!

Does anyone have any idea what I'm talking about?

[Quicksilver]

Compare notes......http://www.xoutpost.com/x5-e53-forum/...eleration.html....

[gmoney]

Thanks QS, but it's not that... I can't really explain it past what I said. It's almost a sound you can make with your mouth if you want... exactly like a trumpet! I know, it's crazy.

[X5FX]

Sounds like your X5 has gas...does it smell real bad too?

[gmoney]

Originally Posted by X5FX

Sounds like your X5 has gas...does it smell real bad too?

That's probably close...

[Quicksilver]

gmoney:

I don't mean to be funny but here's my take.

Noise is one of the more common ways your car will let you know it's not happy. Clicks, clunks, hisses, squeaks, squeals, rumbles, roars — yes, cars in pain do complain, but in their own language. Any of these sounds (or other unusual noises your car may create) could mean your car is heading for a breakdown or a repair. If the sound persists, you need to get the car inspected. Isolate the sound. Is it coming from the front, rear, left, right, under the hood, inside the dash, in a wheel well, from the engine?

After having done a bit more homework perhaps your mechanic can help.

Regards

[rh71]

Only other idea is to run revs in the driveway to see if it's just the engine or else another part because of wind.

[JCL]

To further expand on QuickAG's post, you need to isolate the sound and determine what is impacting it, either in volume or frequency (pitch).

An example would be if the sound is variable with road speed (ie, not dependent on engine speed), indicating it is either related to wind noise or the speed of a rotational item such as a wheel bearing or drive shaft.

Another example would be if it varies with engine speed, in which case you could reproduce the sound in any gear, at any speed, possibly even parked, by holding engine revs at the specific point.

It could be related to throttle position, or engine load, apart from the above two. There are also other variables, but those should serve to start.

You have already linked it to when the engine is cold. The next step is to narrow it down to what alters it, thereby leading you or your mechanic to the root cause.

Diagnostics 101. Hope it helps.

[Fastbuck]

Is your grandma sitting in the back seat?

[gmoney]

Thanks QuickSilver, rh71 and JCL... I'll try and narrow it down further, thanks!