Are you haivng any power problems or is it just the sound gets louder when the engine is hot?

 

i think the engine is toast.

better get a new car.

 

No real lack of power. I feel is has sufficient power for a car with low hp and even lower torque for it's weight.

Kershaw, is that honest advice? We're not looking to put an engine in a car we bought 6 months ago.

If that is indeed what you think, then it'll be traded in next week... As we've already been test driving MX5's

 

Cass just called me from in the car and said this:

- Before it is up to full operating temp, it will not do it in any gear.
- Once it is up to operating temp, it does it in 2nd 3rd 4th etc.
- The hotter the engine gets (heavy load) the louder and more pronounced it is
- The car runs and drives completely fine.
- From time to time even when hot it'll stop making the noise completely.
- When it stops making the noise even when hot, it seems to have a little more power.

This all spells broken catalytic convertor to me. It seems to me like a piece has broken inside the cat, turned sideways and is flapping back and forth under exhaust scavenging and pressure. The reason why it does it only when hot and at WOT is because then it can move, and for the odd time it goes away the sideways piece straightens out. If we can get it to stop doing it from time to time, i'd say the engine is not toast.. But something on or around it is...

Does this not sound logical? We don't want to get rid of the car, we love it. However if it is going to produce continuous headaches like this... We should trade it in.

 

Nothing is wrong with your car. The sound you hear is from the intake. The oem intake is designed to keep the sound down. The reason you have hearing those odd sounds is because you cut a hole and plus you are listening for the sound. When you put the uncut oem intake on and the sound went away that should have been your first clue. Also after driving your car is the cat copnverter red hot?

 

Can you swap your modified airbox assy. onto another car?

 

I sure can and would like to. I almost guarantee it is not a normal noise for an RX8 no matter the intake on the car.

 

Plugs/ Wires/ Coils and Intake have been ruled out.

I took it by Kelowna Motors Mazda yesterday to let the service manager hear the noise. He said it is definately not normal no matter the intake.

We wanted sound, and got sound. With sound we revealed a very real problem with the vehicle. We have an engineer from mazda passing through town next week, he is planning to look at it with our dealership.

No, it did it with the cut stock intake AND the K&N Typhoon that we installed. I'm sure that it does it with the stock one too, we just can't hear it over the wind/road noise.


I'll check tonight when it is dark to see if we can see it glow.

 

wow. this thread is just chock full of logic.

 

It has been thought to be the manifold that others are having to replace for $3200.

Wanted: One stock airbox; so we can sell this piece of **** car and buy a car that is NOT going to always need attention like most others cars who are in this forum.

If I had enough money, i'd pull the piece of **** out and put in an LS3.

 

That's because most dealers don't know how to remove and clean the SSV without pulling the manifold out.


I really hope you do trade/sell the car... cause then we won't need to hear you talking about doing it over and over again... its getting old.

 

Agreed. It wouldn't be half bad if the op would actually listen to advice and systematially pin down the issue (if there is one) instead of wondering around aimlessly, dispensing apoplectic nonsence.

 

Pin down the issue?

Plugs coils and wires were suggested, nearly $500 later... Same issue.

Try a stock intake was suggested. Same noise, 3 different tones 3 intakes later.

Saying i'm aimless in my searches? You people just don't have a clue as to what it is, so you post repetitve yet somewhat rude comments because you are sick of looking at the thread.

Thanks for the help guys, internet forums rarely yield positive results.. This is the worst one i've visited. Good luck when the resale of your cars TANK due to poor reliability.

Lock thread please.

 

I would love to... but you haven't given me anything to work with.
I watched those video clips multiple times and can't hear what you have a problem with.
If you were in Ohio I would say drive by so I can hear it in person... I just don't hear it with those clips.
Can these sounds be heard with the car parked, sitting idle with the hood open, and revving?
That may be easier to narrow down instead of an "in car" clip.

You can always delete the thread yourself

 

Sound cannot be heard at idle, cannot be heard in park at idle or while revving. I've tried revving starting at 5000 rpm to redline, and still can't hear it. It cannot be heard at WOT under 5000 rpm.

The only time it makes the noise under heavy load with a hot engine 5K and above

The heavier the load, the worse the noise. The warmer(hotter) the engine, the worse the noise.

By changing the intake, the noise merely changes tone. Should I try the seafoam trick? Should I check the SSV? And if so, how?

We have a deal setup locally for a trade for an MX5 of the same model year, however it has not gone through yet due to the fact that we do indeed love the RX-8.. We're just scared by their inherent problems.

It dosent help that noone around here knows anything about the renesis engine. Everyone we show the noise to is completely puzzled, as it seems to move pretty good still for a 200 hp/ 130 tq 3000 lb car.

 

Sell it now before it blows up

 

Lots of people here know plenty about it .
You say that Mazda can't figure it out and they actually have the car to work with , so expecting us to be able to do it over the net is a bit of a long shot .
Finding this kind of issue generally comes down to the skill and determination of the person doing the work . Don't blame the forum if you are lacking in this department ......

 

nono, I meant that noone from where I am (here) Kelowna; knows anything about these cars. Everyone is confused as ****, and tells us to run it until there is a failure.

Mazda feels it might be a warranty issue, but because there is no failure yet.. I'll have to pay diagnosis fee... Bullshit.

 

Are you experiencing driveability or loss of power problems? If not your car is fine.

 

We've owned the car for 6 mos. It has felt the same from day 1, however the noise is getting worse. It seems to stumble a little when it is making the noise, however we can still meet the speed limiter at 130 mph without too much effort.

 

Stock airbox went in. K&N filter, two panels from in the box removed.. There is a tiny little bit of sound..

The odd noise is still there. We give up, and are just going to drive it until it pops.. It is covered under the 8 year extended warranty on core engine parts.

 

Any news ?

I have the same problem on my 2007

 

We traded ours in on a 2010 Mazda 3 2.5 Sport.

My dealer was clueless, the local rotary guru was not sure.

I spent close to $2,000 chasing the issue without a resolution, knowing that eventually the noise would end up in a failure. We got into a car that is just as "quick" and is twice as practical for a street vehicle.

GL with your issue.

 

grats on the support... this is in fact a known issue and one i have noticed on more than 1 RX8 in the desert heat.

yes it is very difficult to diagnose and just as difficult to repair any of the possible faulty valves in the intake system.

this issue is accompanied by oil in the intake tract from one of the obvious faulty intake valves allowing the intake pulses to come back through the intake resulting in a lack of power/growl from the engine at high loads at high ambient temps.

if i figure out a quick fix i will update this thread.

 

If you do find a fix, keep the thread updated - I subscribe to it.

We havent had the RX8 for a long time, but we do miss it. I would consider buying another too, but would never buy another 6AT car.

Has anyone considered the torque convertor to be a factor in the noise? Even after trading the car in, I kept watching youtube videos of people with the same issue....

ALL automatic transmission cars!!!

Reading back through the whole thread, the users giving their opinions in this thread were nothing but RUDE. It would be nice to see some real answers/results/ other people solving their issues.