Odd Whine in Mk1 MX5

[The Moose]

Under heavy acceleration (in any gear), my Mk1 MX5 produces a whine (akin to a spooled up turbo)... but I don't have a turbo!! It's a stock 1.8 engine with 40k miles on it.

Any ideas what it could be??

Cheers

The Moose

[rfn]

Do you have an LSD? I wonder if it is the Diff whining??

[neil_bolton]

By the way, whats the easiest way to tell if you have an LSD?

[rfn]

neil_bolton said:

By the way, whats the easiest way to tell if you have an LSD?

One wheel on wet grass, one wheel on tarmac, and accelerate. If only the wheel on the wet grass spins, then you don't have an LSD.

[MX-5 Lazza]

rfn said:

neil_bolton said:

By the way, whats the easiest way to tell if you have an LSD?

One wheel on wet grass, one wheel on tarmac, and accelerate. If only the wheel on the wet grass spins, then you don't have an LSD.

Or, as a friend of mine found out - one wheel on tarmac, the other in deep sand. If you can't get out then you don't have LSD

[The Moose]

LOL

I don't (think!!) I have a LSD. This is a noise that hasn't always been there!!

Any ideas?!

Cheers

The Moose

[Joem]

Is your wife in the car?

[VXRTOM]

Joem said:

Is your wife in the car?

[The Moose]

LOL

Any other ideas?!?!

Cheers

The Moose

[maser_spyder]

The Moose said:

LOL

Any other ideas?!?!

Cheers

The Moose

Lay shaft / idler gear (or something?).

Does it sound gearbox related?


ETA - Maybe a wheel bearing?

Edited by maser_spyder on Friday 27th November 23:50

[WarrenG]

A/C compressor? is it worse on or off?

[Evangelion]

The horrible whining noise in my car disappeared overnight after I banned my mum from playing her Chris de Burgh tapes in it.

[MX-5 Lazza]

Does the whine only change in pitch with engine revs as you accelerate or does it change as you change gear i.e. is it engine speed or road speed related?

[The Moose]

MX-5 Lazza said:

Does the whine only change in pitch with engine revs as you accelerate or does it change as you change gear i.e. is it engine speed or road speed related?

Engine speed related *, not road speed. Any gear, and speed, hard acceleration causes it.

Bizzarre.

Cheers

The Moose

* Actually, that's BS. It's down to how hard the acceleration is. Hard acceleration is the cause of it. Bizarre.

Edited by The Moose on Saturday 28th November 22:07

[maser_spyder]

The Moose said:

MX-5 Lazza said:

Does the whine only change in pitch with engine revs as you accelerate or does it change as you change gear i.e. is it engine speed or road speed related?

Engine speed related *, not road speed. Any gear, and speed, hard acceleration causes it.

Bizzarre.

Cheers

The Moose

* Actually, that's BS. It's down to how hard the acceleration is. Hard acceleration is the cause of it. Bizarre.

Edited by The Moose on Saturday 28th November 22:07

Sounds gearboxy to me, but I'm an idiot.

[MX-5 Lazza]

But does the pitch of the whine increase as the road speed rises or does it drop and start rising again each time you change gear? If it's a constantly rising pitch then it's from gearbox back so could be a gearbox bearing, propshaft, dif, driveshaft or wheel bearing. If it drops when you change gear then it'll be gearbox forward ie gearbox, engine, alternator, ac or ps pump etc.

Edited by MX-5 Lazza on Saturday 28th November 23:46

[maser_spyder]

Oooh ooh oohhhhhh, I know, I know.

Sorry, bit over excited there.

Alternator bearing? A/C pump bearing?

That would whine with revs, and more so under heavy acceleration.

But I may be wrong. I'm still an idiot. (see above).

[NiceCupOfTea]

I'd second a/c - mine whines on hard acceleration.

[The Moose]

Should add that I don't have AC (so unlikely to be that!!)

It is sounding all rather technical - I guess I should probably get someone to have a look at it who knows more than I do.

Great. More £££ spent

Cheers

The Moose

[MX-5 Lazza]

Where are you?