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Strange squeak for 10-15 secs on cold start

Gareth64

Well-known member
Joined
20 Mar 2016
Messages
138
Hi all,

As above, eg first thing in the morning. Loud squeak that ebbs and flows (ie not a constant noise) from the back for 10-15 seconds and then stops. No warning lights, oil pressure good, no warnings, drives perfectly. Serpentine belt only a year old.

I have an audio file but how can I upload it? Pics are straightforward but can I do audio files from my iPhone? :?:
 
Starter motor not disengaging/FUBAR'd?
 
email it to me please ..

[email protected]

If its in a format i can use then ill post / advise on it .

You have a turbo so i have an idea already .. need to confirm with the sound track :)
 
what's your dash voltmeter doing whilst this happens?

Started motor would only be about 2 seconds. Secondary air pump about 40 seconds. Looks like the load placed on your alternator is causing your belt to slip but this will be seen looking at the voltmeter. Should ping straight up to about 13.8 volts as soon as the engine starts. If not, tell us what's happening.
 
Amazing Demort! Will do now thanks!
 
alex yates said:
what's your dash voltmeter doing whilst this happens?

Started motor would only be about 2 seconds. Secondary air pump about 40 seconds. Looks like the load placed on your alternator is causing your belt to slip but this will be seen looking at the voltmeter. Should ping straight up to about 13.8 volts as soon as the engine starts. If not, tell us what's happening.

Hi Alex, yep thanks. Alternator only 12 months old but will check voltmeter reading too.
 
If it sounds like a circular saw, it's probably the secondary air pump motor bearings.
That's what mine was..
It went for 10-20 seconds at cold start-up as the motor span up.
re-greased the bearings and it's all quiet again :thumb:
 
Or in wet damp weather it can be water on the drive belt. Squeaking while it slips When starting from cold.

The way to tell if it's that or the secondary air pump is a blip of the throttle makes it worse or gets rid of it. If that's the case then it's possibly damp / water on the belt or maybe a roller tensioner bearing.

If a throttle blip has no effect then it might be the air pump which isn't affected by engine revs.

Edited to add: after seeing you have a turbo. If you look down the slats in the grill over the engine you'll see the engine directly below, ideal to get wet if not garaged. If it's left outside then it's highly likely its damp on the belt. My turbo did that. Others do it. Mine occasionally / predictably did it after rain and parked on the drive but it maybe lasted 5 seconds. More of a high pitched screech than a squeak.
 
alex yates said:
what's your dash voltmeter doing whilst this happens?

Started motor would only be about 2 seconds. Secondary air pump about 40 seconds. Looks like the load placed on your alternator is causing your belt to slip but this will be seen looking at the voltmeter. Should ping straight up to about 13.8 volts as soon as the engine starts. If not, tell us what's happening.

This morning the voltmeter went straight to bang on 14V (well a touch under) and didn't budge. Same noise for 15 secs. Searching the forum it looks like SAI pump as a number of you have suggested but looks like bearings can be greased rather than new part possibly?

I shall await Demort's diagnosis too. Demort - I have a video clip if you couldn't open the audio file!!!

Thanks everyone
 
Does it sound like this:

 
The noise sounds very much like a fan hitting its houseing at times .. secondary air pump is my feeling .

The noise should be more to the o/s/r which is where the pump is.

Idealy you would disconnect the wireing to it then start the car to see if the noise isnt there .. that would prove it .

Its not that easy to get at though on a turbo .

Details here the same as i emailed .
 

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