shift_zoom8

I noticed that immediately after upshifting, the engine feels and sounds a little raspy, almost like teeth clattering very softly. It's very subtle and almost imperceptible. Its easiest to hear and feel this roughness if you accelerate gradually rather than flooring the pedal. There's no mistake about it; it's always there. When the revs gradually move higher into the power band, the roughness disappears and the characteristic rotary smoothness takes over.


Has anyone else experienced this? Is it normal? Is it something in the engine or elsewhere?

KKMmaniac

Yes! I've noticed the same thing, mostly when I'm driving the car carefully during warmup, keeping max. revs to ~3000.

I doubt it is the engine, perhaps in the clutch or transmission, or maybe a resonating heatshield or something.

Yeah, another little idiosyncrasy to add to the list I guess, I'm not gonna worry about it.

Winning_BlueRX8

Same thing happens to me.

RX-GR8

if it is a faint almost pinging sound i have it too.

Scotchee

I think I've noticed this sound as well. It is rather faint and very reminiscent of minor "pinging" on a 4 cylinder piston engine. I've noticed it under similar low-load conditions. The other thing I find interesting is that it happens more in 4th gear and almost not at all in 5th gear. I don't know much about transmissions but I've heard it mentioned in other threads that 5th gear, being 1:1, is special and is somehow straight through which might be why there's less rattling around.

I hope they're just normal noises. If it's normal for a healthy transmission to make such noises then it doesn't bother me since it is so faint.

Psylence

The RX8 gearbox is very smooth and quiet, with the exception of the throwout bearing that is

My other car has straight cut gears, so I'm prolly a little immune to transmission noise at this point!

Nubo

It could be a heat shield. Try very slowly increasing rpms from idle while parked in neutral. If the buzz comes on predictably at a certain rpm range then it could well be a buzzy heat shield or other component that has a resonant frequency in that range.

Aratinga

Mine does it too. When the CEL came on the first time shortly after I got the car, I was listening for anything that sounded like ping and I picked up that soft chatter. It's apparently normal; one buddy of mine seems to think it just might be exhaust gases resonating against the wall of the exhaust manifold (at least, I think that's what he said).

Racer X-8

I've heard it a lot too. Isn't it just when cold? I don't recall hearing it once it's warmed-up. My bet is that it's engine, but I haven't a clue as to just what it is. Intake porting? Sounds just like valve tapping in a boinger, very faint. I've learned that detonation is very bad on apex seals & this has caused me a small bit of concern. I take it especially easy while I can still hear it.

Good topic. I hope that someone who's sure of what this is can pass that info to us here...

mamccubbin

I have noticed the sound as well. I get it as I gradually accelerate. I notice it more in 4th gear, especially when going up hill at a moderate RPM (3-4k). I get the sound whether the car is warm or cool.

shift_zoom8

Thanks for all the responses.


I feel better now that everyone else has it too. So either it's nothing or we're all screwed in the same way.


By the way, I get the raspy chatter whether the engine is cold or warmed up.

shift_zoom8

Wanted to add that I agree it's like a faint "ping."


Some people have said it might be in the gearbox. I'm no expert in car mechanicals, but I just don't think it's in the gearbox. Seems like it's in the engine, maybe with the fuel delivery or something else that interacts with fuel delivery.

SQ88

I also have been noticing this sound when gladually pressed the gas paddle in 2nd, 3rd, and 4th gears. I think it is coming for somewhere around the bottom in the area of the transmission. I don't know much about the transmission especially for rear wheels drive.

This sound remind me of the exact same sound you get on the van/box truck like vehicle especially in heavy load or going up hill.

Gyro

I get that also........some points that I have noticed

-yes.....its like a faint faint ping

- it doesn't occur in a no load sitiuation (like in neutral)

- it is present in a "light load" or light throttle....lower RPM range.

-its there warm or cold

-it does NOT appear to me that its transmission related.

My theory about it is.....

Low back pressure situation in the exhaust system....(namely...the manifold)...causing a harmless chatter.

Have ever revved your engine at a standstil with the door or windows open? Do this and you will hear a exhaust manifold noise that sounds almost like a exhaust leak. How to do this would be to very quikly blip the throttle....depress it around halfway and immediately lift off. Focus your attention on the bottom of the car. You should hear a loose sounding exhaust note from the engine area. When I first heard this I thought an exhaust fitting was loose. I realised that the system was tight however this was a noise from 'within' the system that was audible from the outside. My guess that it is a rotary ...normal sound. Possibly related to the thread starters discovery.

Winning_BlueRX8

I agree, it sounds like a very faint ping. Although I've only noticed it in 5th gear, and not so much any other gear. I'll test it some more after work.