Ticking behind instrument panel

[oldgitdave]

I'm getting an intermittent quite loud 'ticking' noise that seems to be coming from the instrument panel. It's happened on only two journeys, months apart, so far & tends to start at about 70mph. As I reduce the speed it comes & goes & drops out completely at just below 60mph. I'm thinking it's probably temperature related as well as speed due to it only happening twice so far. It sounds exactly like those early cable driven speedometers when the drive cable has worn through the outer sheath. I had this on my first car which was a 1969 Vauxhall Viva. I expect the Z4 speedometers are electronic though so it can't be that, but maybe something in the speedo mechanism?
All the gauges are working perfectly & the needles are rock steady. Any ideas? It's bloody annoying when it happens

 

[Trav]

What about a servo motor gear on your temperature mixing for the air con. There must be motorised stuff at the back of the dash moving air flaps about.

 

[oldgitdave]

What about a servo motor gear on your temperature mixing for the air con. There must be motorised stuff at the back of the dash moving air flaps about.

Well, it was roof up & aircon set to auto. Could that be speed related though?

 

[srhutch]

Check you strut braces where they connect at the firewall, might need tightening.

 

[oldgitdave]

Check you strut braces where they connect at the firewall, might need tightening.

That's an interesting suggestion, I'll have a look in the morning & report back

 

[Trav]

What about a servo motor gear on your temperature mixing for the air con. There must be motorised stuff at the back of the dash moving air flaps about.

Well, it was roof up & aircon set to auto. Could that be speed related though?

I was more thinking of any moving parts that could be in the dash. When you mentioned a speedo cable ticking noise, I thought you were meaning like a plastic gear click. I was just trying to think of something that maybe in the dash.

 

[oldgitdave]

Check you strut braces where they connect at the firewall, might need tightening.

That's an interesting suggestion, I'll have a look in the morning & report back

Well I've checked the strut braces & they're tight. Each nut has a paint mark which is lined up with a paint mark on the strut brace. Got my socket on them anyway just to check. All OK.

What about a servo motor gear on your temperature mixing for the air con. There must be motorised stuff at the back of the dash moving air flaps about.

Well, it was roof up & aircon set to auto. Could that be speed related though?

I was more thinking of any moving parts that could be in the dash. When you mentioned a speedo cable ticking noise, I thought you were meaning like a plastic gear click. I was just trying to think of something that maybe in the dash.

Yeah it could be a plastic gear clicking. Not sure how I'd check that though. Perhaps I'll have to pull the instrument panel & have a look see?

Thanks for the suggestions guys

 

[Trav]

Check you strut braces where they connect at the firewall, might need tightening.

That's an interesting suggestion, I'll have a look in the morning & report back

Well I've checked the strut braces & they're tight. Each nut has a paint mark which is lined up with a paint mark on the strut brace. Got my socket on them anyway just to check. All OK.

Well, it was roof up & aircon set to auto. Could that be speed related though?

I was more thinking of any moving parts that could be in the dash. When you mentioned a speedo cable ticking noise, I thought you were meaning like a plastic gear click. I was just trying to think of something that maybe in the dash.

Yeah it could be a plastic gear clicking. Not sure how I'd check that though. Perhaps I'll have to pull the instrument panel & have a look see?

Thanks for the suggestions guys

Hmm. I maybe would try a few other things first. What about getting it up to 70, push in the clutch and see if it dies away with the revs. That would rule out engine. Get it up to 70 and wobble the steering a bit see if it worsens. Windows up or down is noise louder. Turn all air con off. Try different temperatures and move airflow around on the controller.

 

[oldgitdave]

[/quote]
Hmm. I maybe would try a few other things first. What about getting it up to 70, push in the clutch and see if it dies away with the revs. That would rule out engine. Get it up to 70 and wobble the steering a bit see if it worsens. Windows up or down is noise louder. Turn all air con off. Try different temperatures and move airflow around on the controller.
[/quote]

Thanks Trav, I'll give it a go. Mine's an auto so I'll try flipping it into neutral & see if it makes a difference. Trouble is it's only happened twice so far & it could be a while before it does it again. I'll let you know .