Weird sound when cold

[AntC]

Hey everyone, I've been having this strange sound at cold start for some time and can't seem to figure out what it is.

I've changed all the pulleys, tensioner, and belt. Have seen some videos on what the water pump sounds like when going bad, but this doesn't seem to be it. I also have a spare water pump just in case.

First time I heard the sound was last summer after the car had been staying under the sun for a day and a half.

I have thought about the alternator, since the sound seems mechanical, but charge voltage is ok.

The sound is only audible until the car heats up.

Would appreciate any tips if anyone has an idea. Video attached.

Cheers

[alankehoe]

My alternator sounded exactly like that for a good few months before it finally died and left me stranded, so that would be my hunch.

I am sure someone will be along to help diagnose this properly.

[ahmed24]

What's the mileage on the car? How long have you owned it and does it still have original alternator? Ive heard a few alternators sound like this as they were going bad and those didn't show voltage issues. 

[AntC]

The car is at 135,000 miles and I've owned it for a a year and a half. Bought it at 120k. Service history doesn't show an alternator change, so its possibly the original one.

Can anyone confirm if part number is DAN1354?

It's not the cheapest part at ~230£ but better to replace it than having it die on the road.

I'm wondering though, why is the sound only audible when cold?

[ahmed24]

If it is the alternator it could be the bearings on their way out. The denso part is DAN1354

That's the one I installed on my car.

[AntC]

If definitely does sound like a bearing which is why I changed the pulleys first.

Will google some more on alternator issues and how to diagnose properly. I doubt I'll be able to head to the garage with holidays coming up. 

Still, would appreciate any additional information before purchasing a new alternator.

Thanks for the quick replies!

[alankehoe]

If you do end up replacing it make sure it’s the denso part. I did replace it first with a spurious alternator which lasted about a week. The denso part has been on the car now for 60000km and still going strong..

[AntC]

Definitely. If it is the original alternator and it's lasted 130k miles, will most certainly buy the Denso one.

[ahmed24]

2 minutes ago, alankehoe said:

If you do end up replacing it make sure it’s the denso part. I did replace it first with a spurious alternator which lasted about a week. The denso part has been on the car now for 60000km and still going strong..

100% stick to denso, I've heard horror stories of unbranded junk. The problem is that the amount of work involved changing the alternator you don't want to have to do the job again anytime soon. So play it safe stick with denso

[ahmed24]

If you do need to buy the denso alternator. Go over to Opie Oils website and fill in the price match guarantee and put the details of this website in https://www.sparkplugs.co.uk/denso-alternator-dan1354

They usually match or beat the price.

[AntC]

Unfortunately I'm not from the UK, so buying an alternator there would be too expensive for me with the delivery and import tax. Will still look for the best deal though.

Thanks for the help.

[ahmed24]

1 hour ago, AntC said:

Unfortunately I'm not from the UK, so buying an alternator there would be too expensive for me with the delivery and import tax. Will still look for the best deal though.

Thanks for the help.

Oh didn't realise you weren't from the UK 🤭

[AntC]

5 hours ago, alankehoe said:

My alternator sounded exactly like that for a good few months before it finally died and left me stranded, so that would be my hunch.

I am sure someone will be along to help diagnose this properly.

Forgot to ask, dis you get the sound only when the car is cold or all the time? Mine only does it for ~5 minutes then it stops. This is what's most puzzling to me.