What Is Causing This Engine Noise?

[phil mcglassup]

Hi All,

I have a Gen 7 with 75 k miles on it but there is a strange engine whine. It can be heard inside the car when driving.

In the video it can be heard best just as the camera points at the engine bay. The microphone is sensitive to the engine rattles which aren't really that bad.

Any ideas anyone? Thanks.

[Ash1502]

what noise exactly are you talking about?

could you narrow it down please

[phil mcglassup]

it's the noise that can be heard as the camera focuses on the engine bay mainly from 19 to 25 seconds on the video.

It's a kind of mid to high pitched rasping whine is the best way I can describe it.

I've already regreased the tensioner pulley bearing so it isn't that.

What else could I look at?

[Devon Aygo]

Without hearing it in person I would suspect the whining noise is a bearing failing in either the water pump or alternator, if at all possible get a long metal tool such as a screwdriver or pry bar and touch it against the alternator or water pump casing and put your ear on the end of the rod you will soon hear which of these is the culprit

[phil mcglassup]

Thanks.....I'll try it tomorrow

[phil mcglassup]

I've tried the water pump and the alternator but I couldn't hear any excessive noises. I heard a slight continuous metallic click from the water pump and a mild low rumble from the alternator but nothing seemed loud or sinister...not unless any of these vibrations are a lot louder when travelling through air!! Maybe the water pump noise is a lot worse than it sounds through the threaded rod I used.

It must be something that the belt drives because when the tensioner is slackened with the engine running the noise stops.

[phil mcglassup]

Any other ideas anyone?

[edwardio]

The tensioners do go on these which do make a noise. It'll be the piston part that will go first.

[phil mcglassup]

So it might be the piston in the tensioner and not the actual pulley bearing!!

Is there any way to test it?