RX8 Knocking
 

New to the forums so hello to all,
Bought a used 05' RX8 MT about 3 months ago. I drive alot for work and this car has been a blast to drive. Bought it at 29k miles and have 40k on it now. Yesterday morning it was a little cold when I left for work. Start the car as normal and left shorty after. About 2 miles later I notice a faint knock that is RPM driven. It is not even audiable at idle but can be heard anytime enigine is under a load. Does not sound like a spark knock, sounds more like a metal to metal knock. I only run 93-95 octane in it so it can't be that. Any ideas on what this could be? I am scheduling an appointment at the dealership on Monday... just worried about what could be wrong with my 8... Thanks..btw... searched the forums extensively and could not find anyone with the exact problem. The car does idle a little rough and hard to start at times.. Thanks for info prior...

If you're talking about the flutter that occurs higher in the rev range, that's normal.

But if you haven't been doing so, make sure you top up your oil regularly!!!

Knocking
 

I thought it was just odd how this just started. Sounds like a metal on metal knock. I had a 3000gt that I spun a crank bearing on once and it sound exactly the same.. I have had no power loss and gas mileage has been same last day or so since it happend. You can hear it in the low rpm range as well as long as it is under a load

and you are where?

beers :beer:

South Carolina.. when I said a little cold it was probably mid to low 40's..

Problem just got worse. Went out today to start up the car to move it out of the garage and all it does is turn over. Went through the clearing cycle like instructed and nothing.. All it does is turn over. Any ideas? Dealership service department is closed on Saturdays, so I am probably screwed until Monday

likely no compression from flooding. also very likely new motor time.. has the last recall been done to it??

beers :beer:

Agree with Swoope on this one - exactly how my first engine made its way to the graveyard.

You guys are right on target. Took it to the dealership today and about four hours later they called to tell me the motor was done. They said that there was almost no compression from either side. He said he was suprised that I even got it to start to bring it in. Motor is on order. Thanks for the help!! I will soon be on my second motor and hopefully that will be the last, atleast for a little while :Eyecrazy:

Hi,

I just purchased a RX-8 2004. I hear a knocking sound coming from the engine around the center of it. Could this be a bad engine. That I'm losing compression?

If I bring it to Mazda, how much will a compression text cost?

Thanks,

As long as you are under the warranty, you would have to pay nothing.

whats up with all the motors blowing? I have been thinking of getting rid of that dang omp and using total pre mix.
oscd

All the motors blowing? It's actually a very small percentage. Keep in mind that no one daily posts "my motor is ok."

But if it will help - my motor is ok. ;)

it would be interesting in seeing what percentage of engines have been replaced in comparasion to other makes. I have a gut feeling it would be high--but I could be wrong.
olddragger

My motor is ok.

But does anyone know about the knocking sound?
 

But does anyone know about the knocking sound?

when its cold like it was for you atleast 40s and lower. Even if the water temp is completely warmed up, it knocks at light throttle at low rpm, load or no load, it knocks for 1 sec then goes away. around 1500 rpms. untill you drive it around for about 5-10 mins.

It done this last winter as well. 89k miles on motor now. damage is done and its only a matter of time.