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Urgent help/advice needed

chriscoates81

Well-known member
Joined
17 May 2013
Messages
1,112
Hi guys, this morning i was moving the turbo around and a kind of whirring noise started happening. It was raining last night but this noise has been coming in and out for about a week (albeit not as loud). I had a listen outside the car and it doesnt seem any louder than normal, my first guess is a idler pulley, any other ideas? Ive put it as urgent as hopefully somebody is coming to buy the car on saturday (bloody typical) and i could do with some help and/or advice.

Cheers
 
Does it sound like an electrical whirring or more mechanical?

Not got a turbo but on occasion I get a whirring which sounds more electrical on start up, lasts about 30 sec and then slowly disappears
 
TBH initially I thought it sounded quite electrical (think moon buggy kind of sound). Not 100% now tho. Would electrical mean alternator whine, I'm hopeful it's not serious.
 
There are lots of things it could be. Ideally you should get someone else to sit in it while you have a listen and get them to rev it to where the sound is the most prominent.

I have a very faint electrical noise that rises and falls with revs, and I'm sure it's electrical (RF) noise coming from the alternator being picked up and broadcast by the speakers.

If it's high pitched and coming from the rear of the engine then one of your pulley bearings could be dry.
 
Unfortunately I've not got the car til Wednesday so I'll check it again then. I realised when I initially posted it could be lots of things based on my vague discription. I'm hoping the body shop guy might have a better idea as he has it for a few days.
 
Typical eh Chris.

A quick check you can do to eliminate ancillaries is remove the auxiliary belt by using the tensioner, then start the car. The alternator, water pump, idler pulleys, etc won't be driven by the belt. If the noise is gone it's one of them. You can then spin them by hand with the engine off and see which one it is.

If noise doesn't go it's nothing driven by the belt.

DO NOT run engine for too long with belt off as you have no water pump for cooling.

PS Not sure how involved removing the belt is on a Turbo. On a Carrera it's simply a case of removing the airbox then using a spanner on the tensioner, and slipping the belt off. My GT3 was equally simple so as long as none of the extra Turbo gear is in the way, it should be easy.

A fellow turbo owner may have some other ideas. Good luck.
 
Cheers, I'm toying with booking off an afternoon to get it looked at. I'm going to ring body shop tonight and go from there.
 
chriscoates81 said:
TBH initially I thought it sounded quite electrical (think moon buggy kind of sound). Not 100% now tho. Would electrical mean alternator whine, I'm hopeful it's not serious.

Does it carry on all the time, or more like a whine from something which cuts in and out every now and then (but always on when the car starts up from cold), up to the same speed each time?

Like this?
https://www.youtube.com/watch?v=ofZW5Kz7ems

If so I'd say its the SAI pump- can get noisy, and its an easy fix.
 
I'll check the video later but last week was as you describe, this morning the car can't of been driven mire than a mile to the body shop but it sounded louder today. Doesn't sound like that video in the cabin, however I didn't think the turbos had that part?
 
It didn't sound quite so high pitched as that, more electric car kind of whirr/whine. Memory's a bit fickle though since this morning as I was in a bit of a rush. Hopefully I can investigate further tonight when I get in.
 
Just in case you're not aware of this, if you do check the idler pulleys. If they spin freely and run on for a while that's not good. A good one will stop after about one turn.
 
The SAI always comes on at a constant speed when the car is started from cold, and go off after 20 or 30 secs. Then it comes on again from time to time, usually when you come to a halt after a drive.

Does the pitch rise and fall with the engine?
 
Robertb said:
The SAI always comes on at a constant speed when the car is started from cold, and go off after 20 or 30 secs. Then it comes on again from time to time, usually when you come to a halt after a drive.

Does the pitch rise and fall with the engine?

Hmm I thought it did but disappeared after 2000 revs or so. If it's knackered would it stay on longer?
 
It stays on for a set period of time, regardless of engine revs, though you might not be able to hear it in the cabin at 2000rpm

Its not that the SAI gets knackered as such, but the bearings get grotty; remove it, disassemble some of it and spray light grease into the bearing. There is a great how-to which Alex Yates posted a while back, if it turns out to be the SAI.
 
I visited body shop and he said he didn't hear anything unusual. My local garage suggested it could be a low power steering fluid level. Is it true the clutch and the power steering share the same fluid.
 

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