Intriguing Noise
 

My car makes kind of a ticking noise and it has sice I bought it. You can hear it best when coasting to a stop and it is in rhythm with the wheels. The front rotors have been turned and I'm going to get the rears turned too, and I expect this will eliminate the noise. Keep reading.

The noise comes from the front and I figured the master cylinder is making noise from the pulse of a warped disk. Here's the odd part: The noise does not happen with the engine off.

So, I figure it must have something to do with the vacuum booster. Maybe there is a check valve opening and closing. Guesses welcome, all you Sherlocks.


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'83 SC

Thats the little guy that lives in your car saying "Tisk, Tisk , Tisk" what are we stopping for now, this is a Porsche let's get going, I need some I-5.

To new for me to guess.

Randy Jones
1971 911

You mean it wasn't the 'cricket-chirp' in the emergency brake cable spring?

California 1 ... would be MUCH better than I-5!

Super, have you actually tested the engine-off theory at, say 50 mph on a deserted road? If so, it very well may be the brake booster that is trying to drive you crazy!

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Warren Hall
1973 911S Targa

[This message has been edited by Early_S_Man (edited 11-04-2000).]

dos it sound like a flasher relay???

Hey Warren I live on Hwy 101 he lives on I-5, the problem with California Hwy 1 is to many Californians. In the winter we try to run the tourists back to California.

Randy Jones
1971 911

Sorry Superdude if were not giving you much help!

Yes, Warren, it's the cricket chirp. A little chirpier than a relay sound. I do have a brake pulse too so I'll see if the cricket's gone when the rotors come back.

No, I have not tested it at 50 mph with the engine off. the chirping is quite detectable at slow speeds, and the engine on/off test was done at about 5 mph. Conclusive though. Engine on - chirping. Engine off - no chirping. I just thought you guys would find it amusing too.

We all should envy Randy. 101 must be a blast. Twisties like a tire commercial, with vistas that appear on calendars.

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'83 SC

Another possibility --- Whenever I've had ticking noises in rhythm with the wheels I check the tires. Dumb as this sounds it has turned out more than once to be a nail or screw in the tread. Tire wasn't leaking but wanted to --- soon as I pulled it out. Anyway, it's very easy to check --- just need someody to roll it slowly backward while you're in the front looking at the tread from street level for any shiny spots. Once it even turned to be a pebble that just wouldn't come loose without pulling it out with a pair on needle-nose pliers.

I used to run Hwy 101 up the coast, too. There is a downside = You don't want to miss an "out" turn --- you'll get a great thrill when launching over the 1000ft. cliffs. Of course, it will be your LAST thrill (what a way to go?) --- unless you just happen to also carry an emergency hang-glider where the Targa top normally resides! http://www.pelicanparts.com/ultimate/biggrin.gif

Big S - Pull your pads and take a look. When your engine is on the pads are being pressed to the rotor a little more than when off. It only takes a tiny high spot or bent thin shoe scraper to make these anoying sounds.

I have a rotating noise in my 82 . Thought about bearings, brakes..... Does it all the time , clutch in or out ,never really tried with the engine off . OF course anyone normal would think I was crazy and say what noise. My mechanic reckons it's the speedo cable . Very faint , Illl live with it. Maybe thats your problem . Its not a chirp!

I have a rotating noise in my 82 . Thought about bearings, brakes..... Does it all the time , clutch in or out ,never really tried with the engine off . OF course anyone normal would think I was crazy and say what noise. My mechanic reckons it's the speedo cable . Very faint , Illl live with it. Maybe thats your problem . Its not a chirp!

Speedo cable???

SCs have an electronic spedo.

Update: Front and rear rotors are straight enough to go on the space shuttle and the noise persists. It is also synchronized with a slightly pulsing brake pedal. Using the brakes has no effect on the noise.

Wiht straight rotors and a pulsing brake pedal, I think I'm looking at tracking down a stub axle that is not straight. AAaarrrrggghhhh.

I will investigate further, including having the engine turn the wheels with the rear end off the ground so I can hear better. but still, brake pulsing is unacceptable, regardless of how subtle it is.

Any hot tips on (straight) used axle pieces?

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'83 SC

Eureka! The noise comes from the little box that counts miles and turns on the hitech OXS light. Sounds like an excuse for another thread having nothing to do with law or ethics or politics.

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'83 SC