Odd noise
 

The 156 1.9 JTD had started making a very odd noise.

Started yesterday, under heavy throttle, a sort of
shhhshhsshshs noise, best I can describe it is like the
noise of waves receding on a pebble beach.

Only happens under heavy throttle, neutral or slight
acceleration there is no problem.

So, how terminal and expensive is this likely to be?

--
Rob Pearson
156 1.9jtd sportwagon (now)
164 V6 Lusso (gone)

Odd noise
 

R C Nesbit wrote:
> The 156 1.9 JTD had started making a very odd noise.
>
> Started yesterday, under heavy throttle, a sort of
> shhhshhsshshs noise, best I can describe it is like the
> noise of waves receding on a pebble beach.
>
> Only happens under heavy throttle, neutral or slight
> acceleration there is no problem.

Stationary or moving?

>
> So, how terminal and expensive is this likely to be?
>

Probably neither. Sounds like a possible air leak. Had a listen under
the bonnet?
Also, try turning the aircon *right* off.
--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
116 Giulietta 3.0l Sprint 1.7 145 2.0 Cloverleaf 156 V6 2.5 S2
Triumph Sprint ST 1050: It's blue, see.
www.cuore-sportivo.co.uk

Odd noise
 

On Fri, 14 Aug 2009 09:52:20 +0100, Catman
> wrote:

>Also, try turning the aircon *right* off.

That *should* turn off on full throttle anyway. I agree that the
description suggests a high pressure air leak.

I'm guessing, as I haven't looked at this on that engine, but there
should be flexible (rubber?) hoses between the turbo and intercooler
and intercooler and inlet manifold. The joints are usually well fitted
by Alfa so I'd suspect a split pipe.

--
Z
Scotland
Alfa Romeo 156 2.4JTD Veloce Leather
'Oil' be seeing you..
(Email must have the word 'Alfa' in the
subject line to get through auto-filtering)

Odd noise
 

Catman spoke:
> Probably neither. Sounds like a possible air leak. Had a listen under
> the bonnet?

Yes, but under no load the noise only comes in at high revs, so is
competing with the engine noise.

It is like turning a switch, at whatever road speed, or any gear, at
30, 50, 80mph, light throttle is OK, heavy throttle has heads turning
wondering WTF is that?

> Also, try turning the aircon *right* off.

<g> yes, and I did do that - no difference.

It does sound like an air leak though. I shall try to investigate
further over the weekend.


--
Rob Pearson
156 1.9jtd sportwagon (now)
164 V6 Lusso (gone)

Odd noise
 

R C Nesbit wrote:

>
> It does sound like an air leak though. I shall try to investigate
> further over the weekend.
>
>

My 2.4jtd (currently on ebay :( ) had a split in the inlet pipe and made
a sound similar to what you describe under hard acceleration.

I cured it temporarily with duct tape.

HTH

AndyB

Odd noise
 

Zathras wrote:
> On Fri, 14 Aug 2009 09:52:20 +0100, Catman
> > wrote:
>
>> Also, try turning the aircon *right* off.
>
> That *should* turn off on full throttle anyway. I agree that the
> description suggests a high pressure air leak.

Should it? Blimey? Is that just full, or FULL hard in the mat?

>
> I'm guessing, as I haven't looked at this on that engine, but there
> should be flexible (rubber?) hoses between the turbo and intercooler
> and intercooler and inlet manifold. The joints are usually well fitted
> by Alfa so I'd suspect a split pipe.
>

There'd be a potential power loss as well?

--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
116 Giulietta 3.0l Sprint 1.7 145 2.0 Cloverleaf 156 V6 2.5 S2
Triumph Sprint ST 1050: It's blue, see.
www.cuore-sportivo.co.uk

Odd noise
 

R C Nesbit wrote:
> Catman spoke:
>> Probably neither. Sounds like a possible air leak. Had a listen under
>> the bonnet?
>
> Yes, but under no load the noise only comes in at high revs, so is
> competing with the engine noise.

Perhaps it's coming from the cabin?
>
> It is like turning a switch, at whatever road speed, or any gear, at
> 30, 50, 80mph, light throttle is OK, heavy throttle has heads turning
> wondering WTF is that?
>
>> Also, try turning the aircon *right* off.
>
> <g> yes, and I did do that - no difference.
>
> It does sound like an air leak though. I shall try to investigate
> further over the weekend.

I shall check regularly.


--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
116 Giulietta 3.0l Sprint 1.7 145 2.0 Cloverleaf 156 V6 2.5 S2
Triumph Sprint ST 1050: It's blue, see.
www.cuore-sportivo.co.uk

Odd noise
 

Sunbeam spoke:
> My 2.4jtd (currently on ebay :( ) had a split in the inlet pipe and made
> a sound similar to what you describe under hard acceleration.
>
> I cured it temporarily with duct tape.

It got worse on the way home tonight, and the engine warning light came on
at one point. Then it lost power.....
Pulled over, had a look around, could see nothing, re-started it, engine
light off, but the SHSHSHSHSHHS changed, when it was there, I had power,
then it would drop off, and so would the power.

Limped it home, and with the aid of #1 son, we found a split in the bottom
hose - nora clue what it is, but it is a large (100mm diameter?) soft
rubber hose at the bottom front of the engine, from mid-way towards
near-side wing.

There is a definite split in it, and you can see it open when the engine is
revved.

Tomorrow I shall clean off the greasy black gunk it is coated with and
apply some duct tape as a temporary bodge. If that fixes it, then I can
just order one.

--
Rob Pearson
156 1.9jtd sportwagon (now)
164 V6 Lusso (gone)

Odd noise
 

R C Nesbit wrote:
> Sunbeam spoke:
>> My 2.4jtd (currently on ebay :( ) had a split in the inlet pipe and made
>> a sound similar to what you describe under hard acceleration.
>>
>> I cured it temporarily with duct tape.
>
> It got worse on the way home tonight, and the engine warning light came on
> at one point. Then it lost power.....
> Pulled over, had a look around, could see nothing, re-started it, engine
> light off, but the SHSHSHSHSHHS changed, when it was there, I had power,
> then it would drop off, and so would the power.
>
> Limped it home, and with the aid of #1 son, we found a split in the bottom
> hose - nora clue what it is, but it is a large (100mm diameter?) soft
> rubber hose at the bottom front of the engine, from mid-way towards
> near-side wing.
>
> There is a definite split in it, and you can see it open when the engine is
> revved.
>
> Tomorrow I shall clean off the greasy black gunk it is coated with and
> apply some duct tape as a temporary bodge. If that fixes it, then I can
> just order one.
>

Sounds like an inlet to me. IIRC the inlet is lower left innit?

--
Catman MIB#14 SKoGA#6 TEAR#4 BOTAFOF#38 Apostle#21 COSOC#3
Tyger, Tyger Burning Bright (Remove rust to reply)
116 Giulietta 3.0l Sprint 1.7 145 2.0 Cloverleaf 156 V6 2.5 S2
Triumph Sprint ST 1050: It's blue, see.
www.cuore-sportivo.co.uk

Odd noise
 

Catman wrote:
> R C Nesbit wrote:

>>
>> Limped it home, and with the aid of #1 son, we found a split in the
>> bottom hose - nora clue what it is, but it is a large (100mm
>> diameter?) soft rubber hose at the bottom front of the engine, from
>> mid-way towards near-side wing.
>>
>> There is a definite split in it, and you can see it open when the
>> engine is revved.
>>
>> Tomorrow I shall clean off the greasy black gunk it is coated with and
>> apply some duct tape as a temporary bodge. If that fixes it, then I
>> can just order one.
>>
>
> Sounds like an inlet to me. IIRC the inlet is lower left innit?
>

That's the one! :)

AndyB