Steakboy42

Well, a little before christmas I took my car into the dealer because I was hearing a wierd metal on metal rattle/grind sound coming from the engine just before a shift (AT) usually with loss of power and twice it was like trying to accelerate from a stop in an OD gear. A tech rode with me and he called it out as Spark knock. I kept getting asked by the tech and the service guy what gas i used. I told him 93, I always use 93. has anyone else encountered spark knock like this? I'm taking it in tomorrow so they can look at it. hopefully all goes well and they can fix it.

-Steakboy

Terrance26

I kinda had that problem with my AT it sounded like marbles in a blender. Turns out that my PCM needed to be flashed, and it worked great right up until I traded it in for a 6spd. Does the sound happen when you get into to the high rpms like over 6000, then it would start to sputter and lose power. They would ask me all the time what kind of gas I was using.

Steakboy42

yeah, it did. hopefully it's something that simple.

-Steakboy

Steakboy42

I took it today and they said they were gunna replace the cat and see if it helps.

-Steakboy

pcorsaro

You should have your dealer call Mazda or at least the Mazda Dealer in Carlsbad CA.

On 1/23/06 (tomorrow) I am taking it in to have the computer removed and sent to Mazda for an SW update and HW upgrades (I think hardware because the SW upgrade can be done in the car).

As I stated in another thread my dealer has seen this on other RX8s and the dealer said that Mazda said that they will try the computer fix and then possibly replace the engine. The dealer knew all about it since he has worked on other RX8s with the same problem.
I will let you know how it works out.

Best of luck,
Paul

Steakboy42

thanks for the info paul. the dealer is trying to say my underglow is causing it because when they tried to read the comp for a diagnostics test, it wouldn't connect to the comp. The thing is that my underglow is hook directly to the battery (fused of course). i personally think its my computer. I just hope it gets fixed.

-Steakboy

sco

That's easy enough for them to check... disconnect the underglow and see if they can connect. If the underglow was generating enough noise to corrupt the CAN bus you'd be getting a check engine light with Uxxx codes.

Steakboy42

I've never gotten a check engine light. They told me that when I take it up for the cat, to disconnect them. I'll prolly pull the fuse and if they bitch about it Ill throw the fuse at them. Thanks for the info

-Steakboy

pcorsaro

For my RX8 it turned out to be a bad coil and burned plug #1.

The dealer did say that the other RX8 owner that had his computer updated by the factory is running great. On that guys car they replaced some ROMs chips in the computer besides doing a re-flash upgrade.

I am waiting to see if a service bulletin comes out on this subject.

I have not picked my car up, so have to see if they fixed it by replacing the coil and plugs. I am not sure if this is a symptom and not a cause.

Paul

Steakboy42

I had my cat replaced yesterday and i drove home with no problems. This morning when I started her up I had a cel flash and then stay on. this freakin sucks. I knew I was a little low on oil so I dropped in a qt and the light persisted. the car seems to be running ok, but you can't really argue with a cel now can you. I'm so frustrated right now. Is there anyway to get the error code without taking it to the dealer?

-Steakboy

rkostolni

advanced auto parts will pull the codes for free.

Steakboy42

thx

zoom44

hymee sCANalyser harrison Canscan...