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Turbo Whine / Oil Leak

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Hi, I'm looking for some advice please. I serviced my S-Max 09 TDCI 2.0 130 yesterday and noticed an oil leak on a pipe heading up the back of engine towards the drivers side. I also changed the auxiliary tensioner and the oil was very noticeable from the side. I think it's an intercooler pipe but visibility from underneath and from the side is very limited to trace the leak up the back of the engine. I've attached some images which I appreciate aren't great but you can see the particularly oil stained pipe.

image.thumb.jpeg.84ee55b6fcb57acc4b476d985e5603f2.jpeg

 

Additionally, about 4 months ago the car would occasionally go into limp home mode - it only ever happened to my wife and always in the same place, after climbing long hill. I can't remember the fault codes now but seemed to be turbo and throttle body related. As a quick fix I bought some Wynns Diesel Turbo Cleaner fuel additive which seems to have sorted it. However, what I think is a turbo whine has started since then. It's like a siren that changes pitch with sound of the revs. Goes up in pitch while accelerating and down in pitch when decelerating. It's more prominent for the first few minutes of driving and then gets quieter but still remains.

It hasn't got any worse in the last few months and the car, other than a bit of a judder in 4th when barely pressing the accelerator - at 35 ish, seems to drive fine. It has power and it's seems ok.

I was wondering if anyone could verify what that pipe is from the first image and offer any advice in general about the siren? We're driving to Spain in about 6 weeks :oops:

Thanks very much.



  • Author

image.thumb.jpeg.411afe9d4f599fb0005dc8db339fa2f1.jpeg

I think that's two separate leaks?  First one is definitely a boost pipe, it's the main outlet pipe from the turbo.  But I can't see the oil from that leak ending up over by the crank sensor?

Anyway, for the first leak, you may find the jubilee clips are just loose, worth trying to nip them up a bit.  If that doesn't solve it, then either the small silicone connector has split (about a tenner on ebay aftermarket) or the plastic pipe may have split.  I've linked the genuine full setup below, including the plastic pipe and silicone connector.

Image 4 - Genuine Ford Mondeo Estate Mk4 Galaxy S-Max Mondeo Mk4 Intercooler Hose 1490848

Genuine Ford Mondeo Estate Mk4 Galaxy S-Max Mondeo Mk4 Intercooler Hose 1490848 | eBay

 

Turbo whine is an interesting one, some turbo's whine for years and work perfectly fine, others whine for a week and then fail altogether.  Almost impossible to know which type you have sadly! :sad:  I'd like to be optimistic and hope that it's been like it for ages, but you're only know focussing on it since the other issues...

  • Author

Thanks for your reply Tom, very much appreciated. I've given it a good run today and it's driving well. Here is a video with the turbo whine. The car was warm by this point but still quite audible - it sounds more like radio interference, although I'm sure it's not.

Regarding the leak(s), it seemed to me that the leak was coming from above that joint on the intercooler pipe and coming down but I could be wrong. I thought perhaps it had found several paths down and that's why it's showing in different places. If it was coming from higher up, would that pipe go up to the turbo and therefore the leaking from the turbo itself?

Time was against me yesterday and the rain kept on stopping and starting so I perhaps didn't investigate as well as I could have. I'm going to have another look at the weekend to see if I can clean it all up and make more sense of it. Oil level hasn't been dropping that I've noticed and the undertray doesn't have pools of oil, so I don't think either leak, if there are two, are substantial.

  • Author

Does a turbo whine on deceleration? I'm starting to wonder if it's something else if not.. it's definitely linked to engine speed.

Worn timing belts and/or worn auxiliary belts whine quite badly often just before they break.

  • Author

Thanks. The timing belt was done 25k / 3 years ago - the car has now done 152k and I changed the auxiliary belt and tensioner on Sunday which made no difference. Stull curious about turbo whine on deceleration. 

Has you alternator got a freewheeling pulley ? Those that have them whine only on deceleration as the clutch inside the pulley wears out. 

  • Author

Not entirely sure, but the whine is up and down with revs

 

1 hour ago, phill29 said:

Does a turbo whine on deceleration? I'm starting to wonder if it's something else if not.. it's definitely linked to engine speed.

Sorry, missed your reply yesterday.

That video does sound like turbo whine.  

Really need to sort the boost leak as that could be enhancing the turbo noise!

 

I do have a couple of old videos that might help you decide...

First one is the alternator pulley on a HDi...they mainly whine on over-run...your whine increases with revs.

 

Second one is the turbo on a Vectra Z19DTH...these things sound like police sirens but seem to work fine! :laugh:

 

  • Author

So the sound is definitely more like the Vectra, however, when the car is stationary it doesn't happen. That's what makes it harder to determine. I have to be moving. I don't think I'll be any the wiser until I have another look at the weekend. It's definitely not been happening for ages, a few months now I'd say. 

 

The wife was just going on the school run. Got her to start it and give it a rev for a minute while I listened and nothing. Then she pulls out and I can hear it as she drives down the road. 

5 minutes ago, phill29 said:

So the sound is definitely more like the Vectra, however, when the car is stationary it doesn't happen. That's what makes it harder to determine. I have to be moving.

That's very interesting.   Boost is limited while stationary on modern cars (to keep the emissions down and stop you wrecking the clutch & gearbox with a launch) but there should always be some. 

I'm still going to stick with boost leak for now and see what you find at the weekend.

  • Author

One more question if I may. If the issue is above that split - 

image.thumb.png.a4a62606ac0ab4e4b2931250fa5b5344.png

 

is it possible to get to that from above? Just wondering how to tackle it.

It looks like a right pain to access unfortunately.  I haven't worked on an SMax so can't offer any experience myself.

I don't think you'll be able to reach it from the top but it's certainly worth a look.

  • Author

Thanks. I've been googling Turbo change on the smax but strangely can't seem to find anything. Thought it might give some insight as to whether it's a massive strip job.

You say the timing belt was done but with the amount of oil leaking around the timing belt cover if it’s getting inside that could cause premature failure of the timing belt.

  • Author

Thanks. I hadn't considered that 🥴 

  • Author

Forgive my ignorance, but does the timing belt speed differ with engine speed. I'm trying to understand if the whine would differ in pitch in relation to revs if it was coming from the timing belt area. Looking at this video you've now got me concerned - 

 

22 minutes ago, phill29 said:

Forgive my ignorance, but does the timing belt speed differ with engine speed. I'm trying to understand if the whine would differ in pitch in relation to revs if it was coming from the timing belt area. 

Probably best to stick to one problem at a time for now.

The timing belt speed changes exactly in line with the revs.  The turbo speed has a slight delay compared to the revs as it takes time to spool up, and then a delay as it slows back down gradually again.

  • Author

Right, so I had a good look on Sunday and cleaned it up a bit. I couldn't find any splits in any hoses at all. It appears as though the leak is coming from a small hose between the intercooler pipe and the turbo - https://www.ebay.co.uk/itm/133959041529?hash=item1f3094c1f9:g:B6YAAOSwJRhhsfT4 but the leak isn't substantial. 

image.thumb.jpeg.f649d330d0180936eb1a17b125902cf9.jpeg

I couldn't feel or see (with a little dental mirror) any splits. I tried to tighten up the clip on the turbo side, but the plastic screw would only go so far and slip, so had to just get it as tight as much I could before it felt like it would slip again. The clip the other side wasn't accessible, I couldn't get a socket on it. 

In terms of performance, the car feel the same. No loss of power. On the motorway you wouldn't know any difference and I can't hear any whining. 

I'm leaning towards turbo over a belt whine. There's definitely a slight lag in whining and engine speed. Also to clarify, I can get the noise to occur when not moving, I just have to rev up to over 3000 and drop off immediately. It seems to whine at lower revs when actually moving. 

So I'm a bit conflicted. If I didn't have a big 2000+ mile drive to Spain coming up I'd just leave it and see what happens - which I think I'm leaning towards doing - but the obvious worry is the turbo failing somewhere in Europe.  

 

  • Author

The other leak seems to be coming from here -

image.thumb.jpeg.99f0e7a31921d9e258ab9b9bd35bfe92.jpeg

Can anyone throw any light on what might going on there please?

 

Boost leaks don't need to be visually substantial.  If the system isn't air-tight under pressure it'll be losing boost when loaded up.  The boost escaping can easily cause a whining noise (same as to a balloon deflating or kettle whistling).  I'd say changing that silicone connector is the first step...but difficult it you can't access the clip. :unsure: 

Not sure about the leak on the cambelt side.  Really the only oil there would be from the head gasket.  I reckon it's coming from higher up personally.  Cam cover gasket perhaps.

  • Author

Thanks again for getting back to me. I can get to the clip on the turbo side, which I think means I can disconnect from the turbo and drop the entire hose assembly. The only thing securing it to engine in the middle is a bolt. I can can then get to the clip on the hose side. A few questions having never done this before.... I take it that hose is going to be a very tight fit? Is it just a case of pull on the bugger considering limited accessibility? Should I be prepared for oil running out (thinking of the drive and the Mrs castrating me for oil everywhere). Would there be any tricks to getting the new one on - lubricant of some kind? And lastly, going by your initial link, if I was to also replace the clips, what size are they https://www.ebay.co.uk/itm/393529244997?epid=1309763102&hash=item5ba02bbd45:g:MPUAAOSw9UBhJLdJ&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5336640302&toolid=10001&customid=2061X563692X16de61d778dcd5b07c85cd7eb710f6b4 ? I can't find a hose diameter. 

  • Author

It comes with clips doh

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