Intake chirp and rev whine - please help diagnose these sound clips - 986 Forum - The Community for Porsche Boxster & Cayman Owners

ScottAZ · 08-09-2018, 10:11 PM

Hi guys,

I have separate clips of two different, but annoying and maybe concerning noises that I'm clueless on.

The first is a chirp upon an initial blip of the throttle seemingly coming from the air intake. I am de-snorkeled.

The second is a whine that corresponds with the engine's revs. It's the same whether in gear or in neutral, clutch in or out. I installed a 997 shifter today and don't recall hearing the sound previously, but I could be wrong. I recently had my water pump replaced. Could it be the serpentine belt? It's not the transmission right, since it's the same whether in or out of gear?

Sorry for the crappy videos, but I didn't know how else to record the sound. Thanks in advance for any help you can offer!

Alan Mackew · 08-09-2018, 11:15 PM

My 2003 2.7 tip has whined ever since I bought it 3 years ago, it is particularly loud when cold, I have always assumed they all do that having read a road test where the tester remarked that the Boxster makes similar noises to the old air-cooled cars,
Perhaps I should be worrying my service guy has never mentioned it,

Cheers

ScottAZ · 08-09-2018, 11:30 PM

Quote:

Originally Posted by Alan Mackew

My 2003 2.7 tip has whined ever since I bought it 3 years ago, it is particularly loud when cold, I have always assumed they all do that having read a road test where the tester remarked that the Boxster makes similar noises to the old air-cooled cars,
Perhaps I should be worrying my service guy has never mentioned it,

Cheers

Cool, thanks. Does it sound similar to mine in the second video below? It seems more noticeable and whiny in the second half of the clip.

tommy583 · 08-10-2018, 03:36 AM

I would take the belt off to see if both or either of the noises go away. It could be a bad belt or one of the pulleys. The chirping noise could also be caused by a loose spark plug. Both of these suggestions are free and pretty easy to do.

dav9515 · 08-10-2018, 06:05 AM

mine sounds just like yours, it's a 97 2.5

i actually thought at first there was interference from a bad ground like in an aftermarket radio that was not installed correctly but it seems that's just how they sound!

ScottAZ · 08-10-2018, 08:03 AM

Quote:

Originally Posted by tommy583

I would take the belt off to see if both or either of the noises go away. It could be a bad belt or one of the pulleys. The chirping noise could also be caused by a loose spark plug. Both of these suggestions are free and pretty easy to do.

Thank you! I'll replace the serpentine belt today and see what happens. I assume it's safe to run the engine without the belt for a moment to see if the whine is gone? If it is, and therefore it points to one of the pulleys, what is my next course of action?

ScottAZ · 08-10-2018, 11:23 AM

With the engine cover off, it's less of a chirp and more of a sucking sounds. Does it sound like a leak somewhere or is that normal? Thanks!

paulofto · 08-10-2018, 01:14 PM

Yeah that sure sounds like air being sucked in somewhere. Vacuum leaks can be very hard to trace if that is what it is but it sounds like air actually being drawn in to the throttle body or the intake manifold. Maybe a loose clamp?

ScottAZ · 08-10-2018, 01:45 PM

Quote:

Originally Posted by paulofto

Yeah that sure sounds like air being sucked in somewhere. Vacuum leaks can be very hard to trace if that is what it is but it sounds like air actually being drawn in to the throttle body or the intake manifold. Maybe a loose clamp?

I tightened down all the clamps I could see. They all had some room in them but I didn't want to over-tighten so I didn't go nuts. Whatever I did, didn't help. And with the engine cover back on, it's back to chirping. Ugh.

Anker · 08-10-2018, 03:49 PM

Isn't that a crack in the intake manifold connection tube in the front of the video?

ScottAZ · 08-10-2018, 03:54 PM

Quote:

Originally Posted by Anker

Isn't that a crack in the intake manifold connection tube in the front of the video?

That?

I think it's some sort of stamping on the rubber. I saw it too, and did a double take. Now, I'm second guessing myself a little.

ScottAZ · 08-11-2018, 12:47 PM

Took the serpentine belt off and the whine is still there. I wonder if it's normal. Or could it be transmission related? I do hear a rattling in the there that sounds like I may have a loose spark plug. I'll tackle that tomorrow. Thanks again for any and all input.