whistleing 850. UK

[bassdiva]

Hi, I have an L reg 850 auto estate, and recently due to the cost of fuel
over here I have started to take my foot off the pedal on down hill runs in
the hope that it gives me just that little bit more to get me to the petrol
station when the tank gets low. I have noticed a whistling sound coming
from under the bonnet when I do this, but it stops when I put my foot back
down a bit.
So you think this is anything to worry about, or a sign that something is
leaking or something?
I do have a problem every now and then with it just cutting out on me, no
matter whether sprinting up the motorway in the outside lane or halfway
round a roundabout. No spluttering or warnings just suddenly nothing there,
could this be connected?
Best wishes for the coming festive holiday to everyone,
Chris

 

[Baz]

Hi, I have an L reg 850 auto estate, and recently due to the cost of fuel
over here I have started to take my foot off the pedal on down hill runs
in the hope that it gives me just that little bit more to get me to the
petrol station when the tank gets low. I have noticed a whistling sound
coming from under the bonnet when I do this, but it stops when I put my
foot back down a bit.
So you think this is anything to worry about, or a sign that something
is leaking or something?
I do have a problem every now and then with it just cutting out on me, no
matter whether sprinting up the motorway in the outside lane or halfway
round a roundabout. No spluttering or warnings just suddenly nothing
there, could this be connected?
Best wishes for the coming festive holiday to everyone,
Chris

Hi Chris,

I'd be checking the rubber elbow on the inlet manifold at the alternator end
of the motor. It's part of the crankcase ventilation system. It's quite
hard to get to, and it perishes and can act as a reed in a trumpet at times.
In my case it set an engine fault code, forget which one, but to do with
mixture lean at some speeds. But the noise got progressively worse, until
it was very loud. Of course it was loudest under max. engine vacuum.

Try poking the elbow with a long screwdriver or stick with the engine
running. If that's the trouble, the noise will change.

Due to the difficulty in getting to the nipple on the manifold, I actually
got a piece rubber hose and re-ran the line on top of the manifold, to the
(infamous) flame trap near the throttle body. I'm using fuel line this
time, as vacuum line seems to go soft and floppy after a couple of years.

My car is a 1996 10V 850 (Australian model).
Regards
Barry

 

[jon5707]

Run water over the obvious manifold and rubber hoses as most likely its a
vacuum leak .Of couse if your in Victoria make sure you use recyled water