rs10

My car has started to sometimes make a slow ticking noise, especially (only?) after driving on bumpy roads. Especially one uphill cobblestone stretch. When it does, there are roughly 5 seconds between each tick. (I’m not sure if the ticks are evenly spaced, or sometimes it’s 4 seconds, sometimes 7, etc.). I hear it when the car is idling in traffic, at a stop light, etc. Don’t remember whether I can hear it when the car is moving, but getting up to speed and driving a bit usually (always?) stops it. I don’t think increasing the engine speed changes the frequency or sosund of the tick, but I can’t be sure. Probablly doen’t matter whether the clutch is in or out. What’s it sound like? Well, “tick”. A bit like a clock. Also, maybe even more so, like the sounds you hear when you step out of a car that’s just been driven hard and it ticks as different pieces cool down and shrink at different speeds. And does it sound like it’s coming from behind me? Well, yes, but then everything sounds like it coming from behind you when you are sure your engine is out to get you … .

Does not sound like a rattle, by the way, nor like the one claimed IMS death rattle video I’ve found online. Better not be my IMS – I just installed a ceramic bearing less than 6000 miles/1 year ago. Unless the guys who installed it screwed it up … .

Then, sitting in the car with the engine idling, trying to see if I could hear the tick again and better test things like revving the engine, etc., I heard something else. This did sound like a faint rattle. So I put my head lower, and it probably got a bit lounder. So I got out and put my ear a bit below the side skirt right in front of the rear wheel, and I couldn’t hear it. Nor with my ear right behind the wheel. On neither the right side nor the left. Then I opened the engine lid and put my ear near the alternator. And I heard it (or something just like it), even better than in the car.

The Porsche dealer recently told me that either the alternator or one or more of the pulleys at the back of the engine are probably the source of a very different noise which I hear at slow parking speeds (which I suspected was the clutch or flywheel), so perhaps I shouldn’t be surprised to hear something back there while idling. But it is a very different noise.

So I’m wondering, can this rattle be the alternator or the pulleys? Can the ticking? Or what else could this ticking be???

(And yes, I do plan to follow up on what the dealer told me, with either the dealer or a specialist. But with these new noises, I'm starting to get nervous about whether it's even safe to drive there.)

(Car is stock except the ceramic bearing, Wavetrac limited slip differential, Powerflex rear subframe bushings, Elephant Racing little metal thingies to prevent the rear geometry settings from slipping at the rear subframe, magnetic oil plug, Porsche motorsport undertray, and Ohlins R&T dampers. All the bushings are in good shape.)

Any ideas/thoughts/insight would be hugely appreciated!!!

Thanks!

Woodman71

Guarantee you the first reply to this will be "Post a video."

AWDGuy

Yup. Post a video. Otherwise it's a wild *** guess

targa996

rs10

I certainly would (have) if I could (have). But I don't have a video and I don't plan to drive the car before taking it for service. And i don't think I can trigger the ticking just by letting the car idle. The only question is whether to drive it to my local specialist, or have it towed there ... .

Macster

With an unidentified ticking noise present I think to play it safe requires the car be flat bedded to a shop for diagnosis and repair.

Be aware my Boxster developed a "ticking" (like) noise out of the blue. The engine was ok when I drove onto a parking lot and shut off the engine but after I started the engine and left a parking lot there was a ticking noise. Decided to play it safe and had the car flat bedded to my favorite dealer 30 miles away. (This also allowed me to have the tow truck operator drive another mile or so and drop me at my house so I could pick up my other car and drive back to the office.)

When the Boxster was rolled off the truck and with a pretty good sized audience of service management and tech around the engine was started. Crickets.

The tech checked the car over but didn't find any thing wrong. What likely happened is something got blown up into the accessory drive area. During the ride on the back of the truck whatever got caught in the accessory drive got blown out. Had I had the guts to ignore what I considered a too large a risk to drive the car at a faster pace after it developed the noise chances are whatever got caught in the accessory drive system would have been blown out.

SM and senior tech told me it is not uncommon for the mid-engine and rear engine cars to pick up something in the accessory drive. My experience is the ticking frequency was too slow to be something "inside" the engine and in fact I suspected it was something to do with the accessory drive but I didn't think it just a piece of paper or trash.

Gretch

When my water pump began failing The noise was "rotational" and I was convinced it was the IMSB. My indy removed the serpentine belt (after I trailer-ed the car to him) and started the engine............ purred like it was brand new.

if the ticking is not rotational in harmony with engine speed, it may be a baffle in the muffler

Macster

You bring up a good point. The water pump on my Boxster got noisy. It was "rotational" noise and I confirmed on my drive way it was not present when the belt was removed.

Another time I started hearing a deep/dull knocking sound that was not really in sync with the engine speed. At first I suspected it was due to high miles and too much crankshaft end play, but over time I came to realize the noise was from a converter. It was the "brick" knocking about when the exhaust was cold. Once hot the knocking turning into an annoying buzzing. A used exhaust manifold (shaken hard before buying to make sure nothing inside was loose) quieted the exhaust right down and eliminated a persistent though infrequent P0430 error.