I have just had a full engine replacement on my Focus 2008 1.8TDCi after the  internal 'welt-belt' broke (see previous posting).  The replacement engine (same engine code) came from a 2006 model with 80k on clock and now that it is fitted there is a nasty whistle/whining noise when I accelerate otherwise the engine runs pretty smoothly.  The engine was replaced by a mechanic friend who also noticed this noise but could not identify where it was coming from.  He tried removing the auxillary belt to check alternator/water pump? but no change.

In the end he said it might be the manifold/engine interface which apparently doesn't have a shim and thus can take some time to seal-up, so he suggested driving it for a while to see if the noise went away.

The whistling/whining noise occurs in neutral and all other gears, and it is most noticeable when I accelerate hard.  It appears to be more dependent on accelerator rather than engine revs, so if I keep a constant accelerator pressure and change gear the whistle is the same pitch.  The noise is more of a whizzing/whistle and not a whoosh (as per intercooler leak) and at high acceleration the pitch is up there with a dog whistle!

On the way home from work after my first day of driving the car, I was whistling along happily at 80mpg when a saw a puff of grey smoke out the back and hey presto the whistle completely stopped.  No whistle for the rest of 15 mile journey.  Great I though it must have been dirt that has burnt off.  However next day after 15 mins of driving the whistle is back.  Now 3 days on and no improvement.

Any ideas please

 

thanks

6 hours ago, ianc65 said:

at high acceleration the pitch is up there with a dog whistle!

Sounds a bit like the turbo to me. On a lot of cars, the Turbo is clearly audible as a whistle dependent on throttle opening. I can not hear it at all on my 2006 1.8TDCI. Was the turbo from the 2008 or 2006 engines? The metal pipe from turbo to intercooler has some bulges that may be for sound absorbing, perhaps there is some difference there?

Leaks in the intake system, or in the exhaust, near the turbo, could also be a cause.

When the whistle stopped, did the car feel different at all? Odd one!

If I could not locate the leak, I think I would use Forscan to monitor turbo boost pressure, to see how that matched up with the noise. But it still would not really locate it.

 

Hi, I have made a video of the engine noise see below (sound might be better on YouTube http://youtu.be/76RYAnc2t_c)

 

 

Having looked at a few more YouTube videos I have found two videos with very similar sound.  Both these seem to indicate that the problem is with engine to exhaust manifold junction.  The two clips in question are 

https://youtu.be/Iiw-pU6V3xw & https://youtu.be/pb5-HVWDPdw

Comments below 2nd video indicate that engine stud had broken and when replaced and new gasket fitted the problem was fixed.  Does this sound plausible?    

6 hours ago, ianc65 said:

engine stud had broken and when replaced and new gasket fitted the problem was fixed.  Does this sound plausible? 

Sounds reasonable.

When air is forced though sharp edged obstructions, it can whistle. And that joint is close to the turbo, maybe some turbo vane noise can escape. The exhaust manifold joint is pressurised to a similar pressure to the inlet manifold, the turbo needs about the same pressure driving it as it generates.

Though when my 2l petrol engine car had an exhaust manifold leak (broken stud), it sounded like a diesel. Just like a tractor! But the exhaust manifold is not pressurised on a normal petrol engine. Having the manifolds on the back of the engine makes checking the studs a bit hard, but most should be just about checkable, I think.

 

I will take a look to see if any of the studs are loose but it is a bit tight in that area as you say.  Do you know if there is a gasket fitted on the exhaust side?  I did see an exploded diagram showing that there was an input manifold gasket but couldn't see a gasket on the exhaust side - I will check eBay to see if anyone sells them!

 

 

1 hour ago, ianc65 said:

will check eBay to see if anyone sells them!

http://www.ebay.co.uk/itm/FORD-FOCUS-1-8D-Exhaust-Manifold-Gasket-1998-on-JD310-Payen-1257264-6180425-New-/331900567657

Example Only! No particular recommendation.

 

sounds like the small metal circular washer/sealing ring is missing from between manifold and turbo. or the egr tube bolts are loose at the manifold end

I have eventually got around to looking at the engine whistle - it hasn't given me any performance problems just a few dirty looks when driving through villages!!I have checked most of studs that attach inlet manifold to the block and these were tight, the EGR hose connections at either end were tight and I am now looking at the exhaust manifold.

Now that I dismantled most of the parts in this area I can see the inlet and exhaust manifold pretty clearly and I can see 'S' shaped pieces of shim protruding between the two manifolds - it looks like the shim/gasket is a combined inlet/exhaust manifold gasket!  I am guessing this is not right as I can only find exhaust manifold gaskets on E-Bay - I have seen inlet manifold gaskets for other Fords that use the same 1.8TDCi engine (C-Max) which look a perfect fit for the inlet manifold I have but when I type in my car details the website says it is not compatible for the Ford Focus 1.8TDCi and no such thing exists.  So now I'm really confused.

I plan to completely remove both inlet and exhaust manifolds from the engine block and look at the gasket, then replace with the exhaust manifold gasket I bought and not use an inlet manifold gasket.

Does anyone know where I can find an exploded diagram of inlet/exhaust manifold attachments to the engine block?  This might clarify things a bit more

Many thanks

Ian

11 hours ago, ianc65 said:

Does anyone know where I can find an exploded diagram of inlet/exhaust manifold attachments to the engine block? 

Maybe. No guarantee it is correct, but look at:

http://eucatparts.com/?action=cat_ford_unit&s_id_grp=1188051&s_id_model=12

And I have tracked the gasket part no 1113080 to a Ford parts site:

https://www.fordpartsuk.com/shop/ford_focus_mk2_intake_manifold_gasket_lynx_diesel_f_1113080_c_589.htm

on that eurocats images, you can see the circular washer i was refering to on the ex manifold parts image.

Great.  After getting to the back of the engine (not an easy job) I found that the brass clamp that secured the turbo charger assembly to the exhaust manifold wasn't tight.  The securing nut had seized before being fully tight and hence was rattling around.  So exhaust gases were escaping from the joint and making this bolt vibrate in tune with the turbo.

I put on a new locking nut and tightened up properly and the whistle is now gone - thanks guys.

Ian