Engines developed a strange buzzing noise

[Tellso]

First time I’ve taken her out in a few weeks and I’ve noticed the engine is now making a strange buzzing noise on idle. As soon as you add revs it goes.

Trying to think if it could be something I’ve done recently but don’t think they would have caused it. I’ve replaced the aerial wth a new one (which still doesn’t go up and down) including tinkered with the wiring, tinkered with the stereo wiring and changed the steering wheel for an aftermarket one. Don’t imagine any of that would have effected it?

Any help is really appreciated

Here’s a brief video:
https://youtu.be/gi_zkZrYzzw

[aussieGT]

Haven't watched your video but I think the charcoal canister can sometimes make a noise like an angry bee after you have been for a run.

But maybe thats a totally wrong answer and I should stop giving any before I get in too deep

(now I have watched the vid - that doesn't sound like the charcoal canister to me, is it that whining noise you mean? Could be an air leak or a sus bearing, hard to hear without being there)

[Tellso]

Haha no worries, thanks for having a listen. It’s weird, it’s literally the first time I’ve heard it ☹️

When it’s idling the noise was constant but goes as soon as you give it some revs.

It has sat for a while only getting small runs or a warm up run in the garage. Bl**dy uk weather!

Maybe a bearing then somewhere. Could it be the alternator?

[feral4mr2]

almost sounds like a vacuum leak, or a VSV playing up.

you wont hear the charcoal canister of the noise of the engine.

internet diagnosis is a pia.... haha

[Tellso]

🤔 now you mention it the idle was a little erratic. They kept dropping. Also have a small rad leak. Although wrong end for the noise. Gonna pop back out now and see if I can isolate the noise to a specific area. Wish me luck! Ha


Update - Ok. So I’ve been out in the garage and ran it for 15mins. No unusual sound 🤷🏻‍♂️ I let it get up to temp and varied the revs. I didn’t take it out for a spin as it’s blocked in. The rad didn’t leak either but you could see where it has been so that’s next on the agenda. Bit of a mystery. I’m going out later and could take it but worried if the rad completely fails. Uh!

[SuperRedMR2]

I used to get that kind of noise but only when I turned the engine off.

Sounds like something else is blowing as well.

[Tellso]

I used to get that kind of noise but only when I turned the engine off.

Sounds like something else is blowing as well.

Really?? I’ll just keep an eye on it then for now. But its interesting you say it sounds like something else is blowing as it is a bit ticky/ tappy and has been since I got it. It’s had a new exhaust below the manifold. Maybe manifold possibly?

[ufer]

I had equal noise but not exactly the same. Especially in Summer or when the motor is very hot. For me it seems as an alternator bearing but it could be also worse - more important bearings. I made only one small trick - higher idle with 20-30 rpm more. Now i have no the bad noise...

[Tellso]

I had equal noise but not exactly the same. Especially in Summer or when the motor is very hot. For me it seems as an alternator bearing but it could be also worse - more important bearings. I made only one small trick - higher idle with 20-30 rpm more. Now i have no the bad noise...

Interesting you say this. I had some work done at my local mechanics and asked him to look into this noise. It only happens when it's been running for a while or idlingfor a while. He said they managed to hear it and believe it to be the alternator bearings getting hot.

The alternator seems to be charging ok but I guess that still means new alternator?

[jimzzr]

I bought a set of new alternator bearings a couple of years ago, prob off ebay. I seem to remember they were a bit pricey for small roller bearing but weren't a common size. Easy enough to fit with care and a small puller