964 Turbo - Odd Noise When Closing Door.

[benny.c]

In the last few days my 964 has developed an odd problem. Well, not a problem as such, but an annoying noise. When I shut either door, there is a loud metallic "click" from the right hand rear corner of the engine bay. It is definitely not coming from the cabin but I suppose it could be the bulkhead area. The car has no sound deadening so I think I'd know if it was in the cabin.

The weird thing is though, with one door still open, or either window wound down an inch, there is no noise. Rocking the car doesn't reproduce the sound and coupled with the above, I guess the pressure building up in the cabin when you shut the door, is causing the noise, but I've no idea what it could be.

Any ideas? The rear and quarter windows are perspex although I can't see what difference that would make. The sound is a mechanical click, like two pieces of metal hitting each other, rather than anything electrical. Central locking etc has been stripped out in any case.

Edited by benny.c on Thursday 17th December 23:04

[graeme36s]

Hi Ben. I have no idea what the cause of that noise is but they all do it. It's like a little metal pendulum that tinkles when you shut the door. My 964 3.6 turbo did it, my mates 964 3.6 turbo also did it. Would be nice to find out what it actually is.

[benny.c]

Not the old..."they all do that sir"

Your description "..a little metal pendulum that tinkles.." is exactly the sound. Shut the door and then wait for a split second before it makes the noise. Very odd but at least I know I'm not alone. I've had the car for a couple of months and not noticed before but maybe it's always been there.

I may get Tech9 to take a (very) quick look when it's having the tappets done after Christmas, just out of curiosity.

[marky911]

Mine too! benny.
Let us know if it's something that can be eliminated.

[benny.c]

marky911 said:

Let us know if it's something that can be eliminated.

I'll split Tech9's hourly rate with you for the solution

[boxsey]

It's the sound of the flapper valves that direct the heat from the heat exchangers to the cabin or to the wheel well. Perfectly normal. The time to worry is when you don't hear it which means that they have corroded and stuck in one position.

[graeme36s]

nice one boxsey

[benny.c]

Cheers. That's that then

A bit of heat is good with the weather at the moment. Mine's had the heater stripped out though, which makes it kind of frosty in the cabin.....and the buckets are too small to wear a thick coat.

Worse thing is, I may be forced to buy some driving gloves to keep my hands warm. Never thought I'd see the day

Edited by benny.c on Friday 18th December 00:05

[sal 965]

boxsey said:

It's the sound of the flapper valves that direct the heat from the heat exchangers to the cabin or to the wheel well. Perfectly normal. The time to worry is when you don't hear it which means that they have corroded and stuck in one position.

+1

[PindiXpress]

benny.c said:

Cheers. That's that then

A bit of heat is good with the weather at the moment. Mine's had the heater stripped out though, which makes it kind of frosty in the cabin.....and the buckets are too small to wear a thick coat.

Worse thing is, I may be forced to buy some driving gloves to keep my hands warm. Never thought I'd see the day

Edited by benny.c on Friday 18th December 00:05

Respect for taking that beast out in this weather

[boxsey]

PindiXpress said:

benny.c said:

Cheers. That's that then

A bit of heat is good with the weather at the moment. Mine's had the heater stripped out though, which makes it kind of frosty in the cabin.....and the buckets are too small to wear a thick coat.

Worse thing is, I may be forced to buy some driving gloves to keep my hands warm. Never thought I'd see the day

Edited by benny.c on Friday 18th December 00:05

Respect for taking that beast out in this weather

+1

I recently had to drive mine when the HVAC wasn't working. That was enough to persuade me that a rear blower bypass is one weight reduction item that I won't be doing!

[robmug]

I seem to remember on my 964 that if you closed the interior air vents this noise went away...

[benny.c]

boxsey said:

PindiXpress said:

Respect for taking that beast out in this weather

+1

I recently had to drive mine when the HVAC wasn't working. That was enough to persuade me that a rear blower bypass is one weight reduction item that I won't be doing!

Everyone says Porsches don't like being sat around and should be driven, so I do my best When it's a nice day there's no way I'm going to leave it sat in the garage, even it is bloody cold.

I did notice one other problem today too. There's no sun visors and at this time of year, that is really quite annoying. Time to get a sun strip put on the windscreen I think.

robmug said:

I seem to remember on my 964 that if you closed the interior air vents this noise went away...

Can't do this on mine unfortunately as fitting the cage meant removing the outer two vents. Just got hoses now with no way to close them off, other than stuffing a rag in them.

[michael sundler]

boxsey said:

It's the sound of the flapper valves that direct the heat from the heat exchangers to the cabin or to the wheel well. Perfectly normal. The time to worry is when you don't hear it which means that they have corroded and stuck in one position.

I now have a cabin heating issue and just noted the absence of this door closing clunk on my 964 turbo so suspect the flapper valve(s). How where can I access it/them. Really grateful for any input.

[Slippydiff]

Here's your starter for 10.
No doubt the exhaust manifold design on the Turbo will be different to the NA C2/4 cars, but the location of the flapper valves should be broadly similar. This should help :

https://rennlist.com/forums/964-forum/235817-964-h...