It sounds like a coffee machine that's almost done making coffee.

Well.... had some misfires now....

And today, it sounded more like a machine gun than a coffee machine....

Made an appointment with the dealer....

The sparkplugs are suspicious i think....

Spark plugs should last 30-37K miles, unless they've been flooded.

The machine gun sounds like MIAC(Marbles In A Can)detonation. What gas were you using reg-87, mid-89, prem-91?

ok guys well my car runs great and only makes a wierd pinging sound when im on the freeway going like 75 and accelerating in 6th gear...sounds like little explosions under the center console area like in the exhaust manifold,,,,,my car is a 2004 with 65k only mods are a typhoon 2 and a rp highflow cat,,,other than that it runs great :Eyecrazy:,,,,,,,,,,oh ya and the plugs only have like 15k on em and the coils are only about 5k miles old they were just replaced

95 ;) That's why I think pinging, knocking or detonation whatever isn't the problem.

But I had some problems with one of the plugs before.... the contact point between the plug and the wire was a bit rusted and stuff. Gave some misfires when I was running like 120 mph, dealer cleaned it and no more problems.... but now I've got this... So maybe it's that damn plug again...

Btw, idle is not silky smooth, and i can hear a slight ticking noise when idling as well ... big chance it's one of the plugs...

Ah well, I hope the dealer finds out.

And it happens ONLY on WOT. And not in 1st or 2nd gear.

Here's a cat rattle for y'all..

if you bottom your car out enough, you will bend in the cat heatshield just enough that when the internals of the cat vibrate, they will resonate against the heatshield. Nothing is "loose" per se though.

It sounds like metal hissing noise, almost like an exhaust leak, and appears only when you step on in certain RPM ranges (as well as when you lay off the gas all the way).

Ok, got back from the dealer, and turns out one of the leading plugs was pretty fucked, and the other ones were a bit dirty. All four were replaced, and no more problems now :) The noise is completely gone :)

Idle is a bit smoother again, without the 850->750 drops, and the ticking noise is almost gone (the faint ticking noise that remains is normal, injectors)

And the sound comes back occasionally after 2k miles.... damn :(

yeah mine does it from 6500 up or so. Most noticeable at WOT. I think it's #2 but dealership wont even bother looking at it to burp the cooling system

I'm gonna replace the coils next week. Will update.

I had a 'marble' but only when I turned on the air conditioning fan. Found that an acorn had gotten into it some how!

Since changing over from Toyos to Cooper tires I have developed a buzz on the passenger side dash - I think it is caused by resonance to vibrations caused by the harder tires...

Well, i have replaced the coils. The old ones didn't seem too bad....

Testdrive tonight.

Did a testrun, and so far everything seems fine :) Keep my fingers crossed though.

Ow the idle is better too. It used to fluctuate just a little at times, and that's gone now :)

In some cases this MIC can be Heater Hose related...see this link on repair Fix..

https://www.rx8club.com/showpost.php...&postcount=295

Ash is posting with the speed of light. All the "Marble" threads are under scrutiny. Carry on.

:rollingla Yes, he certainly is!

Good job! :worship: