Sturmgezhutz

Hi, im new here so i don't know if there is threads already about these but i'll ask anyway...


So few days back i started to accelerate from lights and rev it to about 7000rpm in 2 gear and when i were going to change to third it started to make sound like theres a rock in the lawnmover... so i assumed the engine were done..

But everything worked just fine, no CEL, no nothing... except the huge rattle, kling klong sound it was making..

so i stopped and checked that there is oil and etc.. everything was fine..

engine started normally and runned perfectly.. so i drove the car to my garage and the sound were going away.. slowly, but the sound was going away..

soon it only made this little rattle like sound like something is loose...

i assumed it's the catalytic converter and i took the insides of the cat out today and it still makes this weird rattle sound.. it goes up and down how much rev's i give it...

could it be clutch / gearbox problem??? or just some heatsink loose making rattle sound?

Engine runs great, all gears works fine? no CEL warnings? but still... hope you guys know little better then me..

this is my first rotary powered car so i don't know everything about it but fairly something...


Please tell if you have any ideas what this could be

and Thanks!

Sturmgezhutz

And it's the high power model...

vlad0691

iTrader: (1)

Does it sound like its coming from the passenger side? Could be your SSV.

Sturmgezhutz

This is imported UK model so it's RHD, so then it would be my driver's side what you mean?

i can't pin point excactly where it s coming but somewhere around there?

what is, or where is SSV and what does it do?

bse50

The ssv is one of the intake valves. The workshop manual will tell you which one.
It may be that or a failing catalytic converter. It may even be a misfire, they often come undetected by the pcm.

Depending on the type of sound it could even be pinging.

Sturmgezhutz

Failing catalytic converter it cant be, cos i destroydet the insides of it just today..

it's all empty now

So if it's misfire or the SSV is it something to worry about or can i still drive normally so it won't break anything that's expensive 8-)

bse50

you have to fix what's broken.

Sturmgezhutz

really?

that's why im here for :D trying to get help what to fix

but you said it could be misfire or SSV, not what i could about it...

and don't say "well, fix it"

where to start, how to check?

im not going to randomly start buying parts and replaceing them.

RIWWP

iTrader: (2)

It's more likely to be your SSV. If it was a misfire severe enough for noises you would probably have been running into CELs for misfires quite a bit over the last few thousand miles. Since you didn't mention that, I'm disinclined to think that it would be a misfire.

Rattling from an SSV is when the SSV is basically free floating without any control around it, and the vacuum changes from the engine are just banging it open and closed quickly. Often described as MIAC (Marbles in a can). As yours is a RHD, it would sound like it's coming from directly in front of you about 2-2.5 feet. Driver's side, hood open, follow the black plastic UIM (upper intake manifold) to where it meets the metal LIM (lower intake manifold). The valve is in the LIM, near the top.

The issue could be the actuator solenoid, or carbon damaged the valve itself to the point that the mechanisms are done. A dealer in the US would charge $2,000 USD (not sure what prices would carry over) for clean/repair, though you can usually DIY it for far far cheaper. If it's the actuator itself, it's far simpler and cheaper to fix.

There is an entire DIY thread on how to test it.


Ignoring it isn't inherently bad, but you aren't doing your engine any favors. It would also be recommended that you not go full throttle past where it starts happening, since it's basically wrecking havoc with the air flow, and it's theoretically possible that it could be creating lean and rich spikes as the ECU fights to control the fuel flow. I'd get it tested.

Sturmgezhutz

it sounds right what you are saying...

But the rattle starts from idle to 2000-3000rpm... it doesent rattle so much while driving normal speeds.. or i just can't hear it... don't know for sure...

Have to look in to that...

wheres that DIY thread located here? url?

RIWWP

iTrader: (2)

hmm, SSV only actuates over 6,500rpm, so if you are getting the rattle that low, then it is likely something different. It's possible that it's seal chatter, which would pretty bad new for your engine. Could also be one of the accessories, like the water pump or alternator failing.

Noises are really hard to diagnose accurately on the web without a video or audio clip.


Rather than hunting for the link, I'll show you the best way to find something on a given website:

Google this: site:rx8club.com DIY MIAC SSV

Sturmgezhutz

i could record a video and try to catch that sound / rattle so it would be easier for you guys to help me...

but it is so minor sound so im confident that i won't be anything big (i hope so)...

but better safe then sorry.

my guess were the clutch / gearbox.. mainly clutch / it's pressurebearing or what it's called...

meaby i'lll try to shoot some videos tomorrow or today if i have any luck getting anything good...

RIWWP

iTrader: (2)

It's always possible it's just a bent heatshield rattling on something

Sturmgezhutz

that's what im hoping for... but you never know...

i first thought it were only the catalytic converter.. but after i took it a part the little rattle sound staid...

but i'll get there... sooner or later :D

Gopherage

What about the heatshield on your catalytic converter? If you took it off an hollowed it out and the shielding was already weak or rusted. Maybe when you put it back on it got knocked a bit lose and now rattles.

I don't know exactly what your noise sounds like. But my heat shield fell loose and would only rattle at certain RPMs. Must be a harmonic thing...

Sturmgezhutz

so i took some videos... you can hear the rattle / knocking from them..

not the best quality but, couldnt do better for now...

here 4 pieces, you can tell me if there is something to worry about or if its just something normal..

Sturmgezhutz

the part3 and part4 are the better ones for the sound im telling you about...

Sturmgezhutz

the rattle sound was there before i took the catalytic converter out and emptyed it.. so i think it's not the heat sink of the cat.. it could make some sound, but not the one im looking for.

Footman

iTrader: (2)

More info about your car?
mileage?
when was coils last done?
when was plugs last done?
when were wires last done?

any loss of power?

Sturmgezhutz

-04 high power
88 000km aka ~50k+ miles
coils,wires & plugs done about month or two ago (or so did the guy say, whom i bought this car from..)
everything is written up in the service manual.. have to check.. but it was recently.

no loss of power... for what i know...

Old Rotor

exhaust leak...

RIWWP

iTrader: (2)

Something is wrong. It could be an exhaust leak as mentioned by Old Rotor, but if it's not that, then something is wrong internally in your engine. We shouldn't be able to hear the engine pulsing like that. It should be at a significantly higher frequency. An exhaust leak would make a certain amount of sense, as an unmuffled rotary has been described as "a chain saw attacking a tin shed". An exhaust leak could be letting some of this out.

But again, that pulsing sound is weird. Do some youtube searches for other RX-8 idling. Listen to how smooth those are.

Another possibility is that you have 1 or more spark plugs not firing at all, though I'd expect that would give you a loss of power.

Sturmgezhutz

i thought about that exhaust leak, because it sounds little like that.. but you never can be sure...

i was wondering can it be done by some build up pressure inside the exhaust.. due to the stuffed up catalytic converter?????

manifold cracked or some converter seal blown out?

Sturmgezhutz

this does have a full aftermarket Japspeed RST exhaust system.. not the OEM one...

Sturmgezhutz

and if im correct, RST does happen to crack if it's on a pressure build up / vibration...?

well if it's done badly.. don't know the quality of Japseed's exhaust systems but the price tag for this exhaust is ~1200euros aka 1500 dollars about...