Teapot in a Tempest

[m2500tvr]

Got a 280i question. My 280i is making a whistling noise. No, it's
not really whistling any tune I recognize, but there's an occasional
whistling noise that seems to be coming from the engine bay. It
seems also to occur during warm up. It's affected by throttle
position and brake actuation. Depress/release either control and
the noise increases/decreases. It can also be silence by the impact
of driving over rough rough road surfaces.

I'm thinking it may be a vacuum leak somewhere? Maybe one of the
fuel injection or emissions controls? Maybe a cooling system thing,
like a leaky cap or hose seal, but I don't see signs of a water leak
anywhere? The car otherwise runs great. Starts quickly, idles at
950, throttle response is sharp, engine revs smoothly up to 6K rpm,
etc.

Any thoughts would be appreciated.

Cheers,

- SJ
'67 Lotus Elan S3 dhc 45/6201
'76 TVR 2500M 3550TM
'86 TVR 280i dhc

[castorcamber]

If it is affected by Brake application I would look around the brake servo vac pipe firstly, as you say it may be a leaky seal at either end or possibly worn through along its length.

[toltec]

Start off by saying I do not know anything about the 280 specifically so just a couple of guesses really.

Changes when you press the brake - airleak in the servo?
Some leaves/plastic/rubbish caught in an airflow, accelerating/braking/bumps change the airflow and/or move the stuff around so changing the whistle.

Paranoisia - I used to get this with my bikes sometimes.