Odd sound from dash

[JimSuperSix]

Hopefully someone can help me out with this - I can hear a sort of squeaky chirruping sound coming from behind the dash when the car is idling - a little bit of revs (an extra 100) seems to make it quieter for a second or two (can't be sure though), but even when driving / coasting I can still hear it, although it seems that the frequency of the chirrups drops when moving - doesn't seem to be directly engine or road speed related apart from being more obvious at idle and slower when moving, although it could just be that when moving I don't hear every chirrup, just one in three or something.

If I get out and walk around the car I can't hear it at all - the engine is idling quietly with no squeaks etc..

I thought perhaps the fan motor, but turning the fan off makes no difference. The car has no aircon anymore, and has had a new head, cambelt, water pump etc... within about 5000kms.

Is there something else behind the dash that's pumping / spinning / belt driven?

It really does sound like a slightly squeaky belt, but under the bonnet all is quiet.

Anyone have any ideas? I hate the car having noises and not knowing what they are.

thanks
James (2.4 SSR Ltd td auto)

[kitesurf_phil]

I had a similar noise. It turned out to be a slghtly slack belt. Check each belt by trying to twist it between you fingers through 180 deg. The belt should only twist about 90 deg.

I thought I had a mouse nest behind the dash.

[JimSuperSix]

I had a similar noise. It turned out to be a slghtly slack belt. Check each belt by trying to twist it between you fingers through 180 deg. The belt should only twist about 90 deg.

I thought I had a mouse nest behind the dash.

Well I thought it might be the power steering belt (the bracket had snapped in half when I bought the car and thus after bodging it back together the belt runs twisted slightly along its length) but it seemed really odd that I couldn't hear it from outside, just when in the car, but if you had the exact same thing then I guess I'll get at that bracket with new-found welding skills (!!!) and make it straight.

I think either the speedo or tacho cable is sounding a bit rough also - how do you oil a cable? I don't really want to pull the dash apart again if it can be avoided....

[NiftyNev]

I think either the speedo or tacho cable is sounding a bit rough also - how do you oil a cable? I don't really want to pull the dash apart again if it can be avoided....

I have a '92 model and there is no speedo or other cables. It's electronic. What year is yours. It may be the same.

Nev

[JimSuperSix]

It's a H-reg - I think that's 1989.

The speedo needle jumps around a bit at low speeds, but smoothes out past about 20mph - I assumed it was a worn or sticky cable.

[NiftyNev]

It's a H-reg - I think that's 1989.

The speedo needle jumps around a bit at low speeds, but smoothes out past about 20mph - I assumed it was a worn or sticky cable.

'89 model would most likley have a cable.

Nev

[JimSuperSix]

Well, I've done some investigating and am now more confused.

With the door shut I can hear the noise, somewhere behind the dash I think. Open the drivers door and I can't hear it. Open the bonnet and it all sounds fine, no sign of the noise at all. Walk around the car, nothing. Up and down gears, nothing. Lights on/off, windows etc to load alternator - no change from inside, nothing outside at all.

It sounds like something plasticky vibrating - rev the engine and as the car then vibrates at a different speed the noise either stops or changes. A few seconds at idle and the noise is back. I also noticed it slightly when cruising in a high gear (ie. so there is less engine noise), but it sounds the same as at idle, only less frequent.

The only thing I can think is that the noise started after I opened the bonnet to check the ATF fluid. The bonnet hinges are really stiff (let go and the bonnet stays open at 45 degress) so I've WD40ed them and I'll see what develops.

I hate these odd rattles - I always assume the worst

[JimSuperSix]

[UPDATE]

Well, I seem to have cured it (fingers crossed) - WD40 on the bonnet hinges and the noise is gone

Can anyone tell me how to remove the bonnet hinges? They seem to disappear into the bulkhead through some rubbery slots. I'd like to remove them and grease them properly.

[solent_surfer]

In answer to your origional question, i had the same chirping noise for ages, and it seemed to go when you reved the enging. it turned out to be the fan blower which is situated central and behind the dash.
After spending nearly a full day removing the dash and accessing the fan, a little 3-in-1 oil down the motors shaft did the trick and has been as quiet as a whistle since (touch wood).. the easier way of sorting the prob would be to turm the fan on high and spray a little silicone lubricating spray in the air intake at the top of the bonnet (most smell nice)!
I found out the hard way!!! If in doubt wait 'till you can hear it then turn the fan speed up a notch, if it goes, thats the prob.
best of luck