Weird 'chirping' sound, 2001 Boxster S
 

Have had this noise, a 'chirping' sound, mostly at idle, for a good long while now. Why I never looked into it I don't know (always some bigger flame to pee onto??), but it's been around at least 2-3 years now. It's not intensified nor led to any significant issues over that time. I guess that's why I never really worried about it—the longer it went on with no adverse consequences, the more I characterized it as innocuous.

Anyway, my son decided I should look into it. His theory was that it was tied into one of the pulleys driven by the belt—alternator, power steering, water pump, whatever. So, ever since he made this suggestion, I've been planning on doing the obvious: put her into service position, pull the seats forward, pull the carpet and engine cover plate, pull the belt and start her up. See if the noise went away. So—today I finally got around to it. Did all that, and the 'chirp' was still there, even with no belt. So he (and I) are still stumped. He asked if I had posted a question about this (+/- a vid) on 986 and I admitted I had not.

To remedy that situation, here is that vid, made yesterday, of the sound that I've been listening to for a good while now.

Anybody have any theories as to what the source is??

https://youtu.be/f4a8Md4YpuA

Oftern the 'littel bird chirping' kind of sound is coming from a loose sprk plug on these cars.
Re-torque the spark plugs and if one is a bit loose, you most likely have found the reason for the 'chirping sound'...

Interesting, I never would've guessed spark plugs. Wouldn't hurt to inspect or replace your spark plugs, spark plug tubes (or just the o-rings), and coil packs depending on mileage and service history. I'd be worried that taking a coil pack out could kill it if it's already about to die. Could crack the plastic or something like that.

ECS sells ignition kits.

Granted I would only worry about that if the car is 120k miles or more without any ignition servicing. And if you take the spark plugs out, replace those at minimum. No point in installing old plugs given how inexpensive but important they are.

Chirp is gone.

My kid, having read this tread, said we ought to diagnose the problem, at least to the point of checking the loose-plug theory. That's what started us down this pathway that tied up the car for like a couple weeks.

First it was the plugs. Decided to do the coils as well. None of the plugs seemed "loose" but some did come out without hard cranking on the wrench...so they probably were.

Then it's like, "Well, she's on the lift, the water pump is like 11 years old...do we do a WP/thermostat before taking her home?" He's totally game. So then I say, "Well, if we're emptying the cooling system, maybe we should do the coolant expansion tank before it develops the inevitable crack and starts wetting my trunk carpet." The kid's like, "Sure, let's do it."

It's absolutely terrific having a son that likes to wrench! :dance:

Frodo, it's actually a blessing as I have to beg my kids to help me with the heavy wrenching (suspension repairs, etc.,) and now that both live out of the house is harder, aging sucks.. :ah:
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