Strange whirring noise from engine c70 t5

[thad1]

hi guys,
I have a c70 1999 model T5 GT with 100k miles full Volvo history etc
I think the car is developing a strange kind of whirring noise from the engine, not sure exactly where it's coming from but seems to be right in the middle or slightly towards the rear. It sounds kind of hollow!
I have made a short video so you can hear it for yourself!!
The engine sounds a bit rough in the video but to be honest it's very quiet apart from the injectors which are very noisy, the whirring noise in kind of in the background!
Any help/advice would be great!
Thanks
here is the link to the video
http://s1119.photobucket.com/albums/k629/thad11/?action=view&current=video-2012-02-20-16-20-42.mp4

[daza-b]

weird one that...turbo??

[thad1]

weird one that...turbo??

Well it's deffo odd lol

Maybe the PCV as it sounds like a hollow sound!

Car has been perfect for the few weeks I have owned it!

Not sure it's boosting right either, seems to rev fine but lacks a bit of trq!

[Wobbly Dave]

TBH I didn't hear much above the rest of the usually engine noise.

If you are local to Shropshire I will happily help out.

[M-R-P]

May be p/s pump or water pump? or has the timing/auxiliary belt frayed and started rubbing on the plastic cover? or manifold gasket blowing from one of the ports?

[Wobbly Dave]

All I can hear is the aircon pump making its usual high pitch whine.

[thad1]

ha ha I can't hear half the stuff you guy's can!
I am going to check and see if the dipstick is blowing anything out and see if the oil filler is creating a vacuum, apart from that not sure what else to check,I sometimes get a metallic noise that sounds like a timing belt cover rubbing but it's on the right hand side of the engine so it can't be that lol

[Dangerous Dave]

Have you checked all the small piping? I had a kinked pipe once that made what sounded like a whirring noise.

[thad1]

I have just checked the PCV and it's all fine, the noise has now gone, I think it's only when it's hot!
Checked the oil level and it's on minimum, I guess if I put the 1.5 litres that's missing in it might not sound so hollow!
I want to replace all the vacuum pipes as well as they are getting old now, can anyone point me in the direction of a good diagram or pictures of where they all are on the car?
I had a Saab 9-5 aero previously and could see all the hoses easily but on the C70 I can't see a b****y thing!

[dalhousie2008]

you should hear mine on a cold morning for noises, i thought it was bad but flyingbrick made me feel much better on sunday lol

[Wobbly Dave]

Most vac pipes relate to the BCS which is strapped to the side of the airbox. Vac pipes run from the actuator & turbine (clean air side) of the turbo. The other one runs to the blow off side of the air intake from the BCS.

There is a vac pipe that runs to the NS end of the inlet manfiold just near to the one that runs to the brake servo.

[thad1]

Most vac pipes relate to the BCS which is strapped to the side of the airbox. Vac pipes run from the actuator & turbine (clean air side) of the turbo. The other one runs to the blow off side of the air intake from the BCS.

There is a vac pipe that runs to the NS end of the inlet manfiold just near to the one that runs to the brake servo.

ok mate that's great!

I am in Banbury by the way, a fair few miles from Shropshire!

[thad1]

OK so as well as this odd noise the car does not pull as strongly as it did and I have vibration through throttle pedal and steering wheel from about 2k revs!
Now I am getting worried!!

[Dangerous Dave]

Is it rough at idle?

[thad1]

Is it rough at idle?

Hi

Yes maybe a little bit, it's only a little bit rough, it still accelerates smoothly (no stuttering on boost etc) it just feels like it's down on trq more than anything!

A month ago it was silky smooth and very quiet all across the rev range but now it seems a little bit rough on idle and almost a bit lumpy at 2k onwards, this is also where the vibration seems to start.

[M-R-P]

could still be maf, or a boost leak somewhere?

[Haizum74]

hi guys,
I have a c70 1999 model T5 GT with 100k miles full Volvo history etc
I think the car is developing a strange kind of whirring noise from the engine, not sure exactly where it's coming from but seems to be right in the middle or slightly towards the rear. It sounds kind of hollow!
I have made a short video so you can hear it for yourself!!
The engine sounds a bit rough in the video but to be honest it's very quiet apart from the injectors which are very noisy, the whirring noise in kind of in the background!
Any help/advice would be great!
Thanks
here is the link to the video
http://s1119.photobucket.com/albums/k629/thad11/?action=view&current=video-2012-02-20-16-20-42.mp4


That sounds very similar to what I have on my S40. Here have a listen http://www.volvot5.co.uk/forums/showthread.php?t=41368 not sure what it is but fuel pump has been mentioned. Now as you said its not boosting correctly and me having my oil return pipe o ring and gasket replaced and pipes checked and cleaned it could be that although my boost seems fine.

[thad1]

That sounds very similar to what I have on my S40. Here have a listen http://www.volvot5.co.uk/forums/showthread.php?t=41368 not sure what it is but fuel pump has been mentioned. Now as you said its not boosting correctly and me having my oil return pipe o ring and gasket replaced and pipes checked and cleaned it could be that although my boost seems fine.

Hi Thanks for that, I am not sure there is a drop in boost now, thinking about it it boosted higher or felt quicker when the temp dropped to -4c, considering it was 17c yesterday I would expect a drop in performance!

I am running it on 99 octane fuel, the difference in performance would be similar to me putting 95 octane in it if that makes sense!

I guess as long as it does not get worse it should be ok

It does sound like it could be a bearing on the way out but I am not sure if there is anything around the back of the engine that is a moving part with a bearing in it!

If it was on the front left I would be thinking tensioner etc

I am just worried it may be a bearing in the engine, but at 100k with a full main dealer history I would be a little bit surprised!

[thad1]

Just a thought but the car was idling on a hill and stopped due to low fuel, I guess this may cause the drop in performance due to crap being sucked into the injectors, could that do it?

[Haizum74]

Hi Thanks for that, I am not sure there is a drop in boost now, thinking about it it boosted higher or felt quicker when the temp dropped to -4c, considering it was 17c yesterday I would expect a drop in performance!

I am running it on 99 octane fuel, the difference in performance would be similar to me putting 95 octane in it if that makes sense!

I guess as long as it does not get worse it should be ok

It does sound like it could be a bearing on the way out but I am not sure if there is anything around the back of the engine that is a moving part with a bearing in it!

If it was on the front left I would be thinking tensioner etc

I am just worried it may be a bearing in the engine, but at 100k with a full main dealer history I would be a little bit surprised!

Yeh I listened to mine this morning and it appeared to be louder near the rear of the car although I can hear it in the engine bay too. I noticed when reverse parking and not fully letting out the clutch it would rise in tone slightly. Still baffling though

[thad1]

Yeh I listened to mine this morning and it appeared to be louder near the rear of the car although I can hear it in the engine bay too. I noticed when reverse parking and not fully letting out the clutch it would rise in tone slightly. Still baffling though

Just a thought but could this be a heat shield?

The noise is still there but it seems to have changed tone, it seems slightly metallic now!

Would it be unusual for the top end to need a rebuild after 100k miles, bearing in mind the car has a full main dealer history?

[Wobbly Dave]

I've never heard of it. T5 is a solid motor. Only issues I have ever heard come from tuning related issues - namely pushing too much boost. I lost an engine to headgasket like-symptoms - however we were tuning it.

I would be v. surprised if there is an issue with the head.

Ancillaries can be troublesome.
Clutches on air-con pumps can go.
It could be a dodgy cambelt tensioner

But I am just speculating. I think the time has come to take it to a Volvo specialist.

[leeboy]

does the engine have vvt as my old s40 made a similar sound and got worse around 3k rpm when it was kicking in. just an idea but dont know much.

[Haizum74]

Well its not the fuel pump, lifted the back seats up and not heard anything. Its definitely coming from the engine side by the sounds of it.

[stevie69]

can you hear it change when you put the clutch pedal in and out?

[960kg]

hi guys,
I have a c70 1999 model T5 GT with 100k miles full Volvo history etc
I think the car is developing a strange kind of whirring noise from the engine, not sure exactly where it's coming from but seems to be right in the middle or slightly towards the rear. It sounds kind of hollow!
I have made a short video so you can hear it for yourself!!
The engine sounds a bit rough in the video but to be honest it's very quiet apart from the injectors which are very noisy, the whirring noise in kind of in the background!
Any help/advice would be great!
Thanks
here is the link to the video
http://s1119.photobucket.com/albums/k629/thad11/?action=view&current=video-2012-02-20-16-20-42.mp4

Your `99 T5 model went over to the VVT with the two part engine cover and it has gone kaput that is the recycling noise on the vid you can hear. It also does prove the point as you say you have lost some torque and this is what the Variable Valve Timing does. If you take off the top covers you will see by the rear cam pully a solenoid with a plug going to it take this off then re start it may stop the noise and also proves the pulley has usually gone, 99% of the time, the solenoid not so.
Forgot to say my S40 1.8 2001 VVT has gone and the sound is identical
Hope this helps you?

[thad1]

Hi
Thanks for the post it's very informative!
Question is how do I fix it?
is it ok to run around with it unplugged if that is the problem?
Would it be ok to raise boost slightly to compensate for loss of power?

[thad1]

I have just had another listen to the engine and to be honest I does not sound like the VVT, there is no rattling from the head, it's a background reverberating noise and it's not anywhere around the head. I have listened to a few clips of failed VVT and it sounds nothing like that!
Also the slight drop in performance I think can be attributed to the weather, it feels a bit less torquey due to the warmer weather I think. It is not boosing as well as it was, the VVT seems to be working fine, I have lots of power/trq between 3k and 6k.
ALso on idle in the car I can't actually hear the engine it's so quiet!

[thad1]

ok so i disconnected the solenoid and there was no change in engine sound, bear in mind there is no rattle from there anyway. I disconnected the boost control valve and test drove it, it felt flat but like it was maybe 2-3 psi down on what it should be, the car does feel flatter than usual but i have been driving it very gently for a week and I find to get it going really well you have to drive it like you stole it for a while before it starts going really well. I checked the boost hoses and they all seem ok, having said that the intercooler hoses needed a fair bit of tightening up, I am just wondering if thecar is not reaching target boost due to a leak somewhere?
I can't honestly see how it's the vvt as there is no rattle from there at all. When i first got the car it felt a bit flat but started to go a lot better after a tank full of tesco 99 and a good thrashing!
Even after this the boost did feel a bit hit and miss at times, just wondering if there is a tiny hole somewhere that has got bigger!

[960kg]

To be exactly sure disconnect the solenoid again and go for a drive, then connect it and go for a drive....if there is no difference in performance then the pulley has gone, if it makes a difference when connected back then you are ok it is working.

[thad1]

ok thats a very good idea!

[thad1]

ok so I took the car to a specialist, he said nothing wrong with vvt, engine sounds normal but agreed there was a background whirring noise, has no idea what it is but thinks it could be a tensioner of some sort, wants £100 to investigate!