SonnyT

Some say "tick-tick" others say "clack clack". Mine sounds more like the latter

I'm going to get a stethoscope, but clearly it's coming from the bottom part of the engine, right where the exhaust lifters should be.

Can the experienced among you please confirm that this sounds like the lifter that's causing the clack? It's fine when cold, the sound starts once it's fully warm/hot.

FYI '97 C2, running 15W50, no heat shield, about 65k miles
Thanks

frankv

Hi SonnyT,

doesn't sound like lifters to me or at least not at all like the sound I had when I had bad lifters. Lifters should be a very rapid ticking that varies with the engine revs, whereas here it sort of seems like a random and deeper clack sound.

What happens when the revs go up? Honestly I have no idea what this is

- Frank

P-daddy

Sounds like someone with a stick tapping on something metallic. I don't believe it's lifter noise. Try to see if you can isolate the sound coming from the mufflers. Maybe something is flapping inside?

Ed Hughes

Sounds like an iPhone moving around a 993 engine. Not a good way to diagnose engine problems.You aren't going to hear noisy lifters out the exhaust either, IMO.

timothymoffat

Like others have said, doesn't sound like lifters from that clip.

matt777

Technically you may be correct but its not a very useful observation

It sounds somewhat random so not likely caused by something in the engine. If you can get it on a lift and listen from below it might help pinpoint the location. Did this sound just start? Was any work done recently to the car? That' all I've got.

Ed Hughes

I'm sorry, but I find it impossible to diagnose noises on a car, recorded on a phone and playing on a computer. Same as trying to evaluate the sound of various exhaust setups. There are pulleys/bearing turning, exhaust gaskets that could be bad; a few things that can go tick-tick or clack-clack.

EckFe1

I have very similar clacking but a lot more of it and on a more irregular bases. I run a LWF so what you hear would be the gears in the gearbox. As soon as I depress the clutch, the noise is gone.
You might want to try that. Maybe your DMF is going bad? Definitely no lifter noise.
Good luck,
Ed

matt777

It will be a forum guessing game.

pp000830

Is it an intermittent misfire as normal at idle on a 993?

BesideTheBox

Exactly! Yes, these are misfires at idle. No guessing necessary.

SonnyT - Switch on your air conditioning and/or your headlights... Does the noise lessen in intensity or go away? Mine does.

Another couple questions...
What type of gas are you running in your car?
Do you have an OBD-II scan tool to observe 'live data'? I'm interested in what your long term fuel trims (LTFT bank1 & 2) look like on your car.

pp000830

“accept the things I should not fix, have courage to fix the things I must and have the wisdom to know the difference”

Andy

SonnyT

Thanks for the suggestions folks. To answer some of your questions, I'm running 93 octane, on the original clutch and DMF, will report back on the other suggestions. Perhaps it's a misfire, but this started in the last couple of weeks.

I'll get underneath with a steth to see where exactly its coming from