The short of it is that the 2009 RX-8 has an issue where the only way to dis-engage the cruise control from the throttle is to turn the car OFF.

Now here is exactly what happened to me yesterday on the highway, I have an 09 RX-8 R3 model with 6K miles:

I was driving on Hwy99, the cruise control was on, I had been using it for about 20 miles, occasionally bumping the speed up or down as conditions permitted. My primary reason for that is on long trips I get better gas mileage that way.

The divided highway came to an end and there was a traffic light about a half mile ahead, so I bumped it down about 2 mph, then bumped it down a few seconds later another 2 or 3 mph.

The light turned red then, so I stepped on the brakes (doing about 65 at this point).
The engine reved up, the cruise control did not disengage so I stepped on the clutch.
The engine continued to rev up so I pressed the cancel button on the steering wheel.
The engine continued to rev up (about 6K now) so I took the car out of gear and turned the cruise contol off.
The engine continued to rev up (about 7K now) and I'm completely stopped at the light. No throttle control at all.
I shut the car off at that point. When the light turned green the car started fine and ran normally. I tried to reproduce the problem (I used to test aircraft for a living, so I was naturally curious) but was not able to easily reproduce this. On Monday I'm taking the car in and having a talk with the dealer.

There is obviously a bug in the electronic throttle code. For all of you out there with the new Series two, if you should run into this problem, put the car in neutral, don't turn it off until you've stopped, otherwise you may lock the steering by accident. Also trying to overcome the engine with the brakes could lead to a dangerous condition.

 

Scary.

 

Not good at all... I'd talk to the dealer

 

for sure take it out of gear! good thing you had a manual.
This happened on me when I worked for enterprise in a car with a diamond as a logo, it was auto and revving too high to disengage to N and I soared off the off ramp.
could be worse, at least it's not a Toyota, they would change your mats for your troubles!

 

Does your brake switch work properly? When you hit the brake the switch tells the PCM to disengage the cruise.

This is a warranty issue ...take it to the dealer and don't drive the car till it's fixed....Likely a problem with your cars hardware

If it is a software issue...Mazda had better figure it out fast and get it fixed before someone gets killed

 

wow, scary.

Be careful, I havent heard of this issue before myself....

 

hummm drove my R3 from Colorado back to Nebraska cruise control all the way, no problem at all.

 

you bought a toyota RX-8 by mistake.

 

Whoah, that does sound pretty scary... I've never used cruise control, but I know a few people do on the highways. If it's not reproducible, that could be tricky.

Diamond as a logo would be Renault.

 

Brake switch is fine. But even then, the cancel button, the Clutch, and the on/off switch all failed to cancel and disengage the cruise control. It is most likely a software issue. Throttle by wire is new after all.

 

The throttle is very redundant.....

Strange though that one of the "off" routines didn't work

This isn't good..potential for catastrophic failure is high


I have a 75YO family friend who had a pedal failure in a Toyota ..she went through a busy intersection and just missed getting killed...totaled the car though. This was before the pedal failure was a known defect..

 

Your car needs an exorcist...STAT.

It is the power of christ that compells you!!!

 

Do youreself and all RX-8 owners a favor and file a report on line with the NHTSA. If they get enough reports of this problem they may do something about it.

http://www-odi.nhtsa.dot.gov/ivoq/

 

This happened to me when I drove my friends Camary.
Gas stuck on.

 

Okay, so I have the opposite issue. I will be driving down the highway and then all the sudden the cruise control will shut off and not re-engage. I have just over 22k. A week ago now, I am also feeling a strange rumble when I start off..sometimes in first and sometimes in second. No, it's not my driving. It feels as if it would be skipping like driving on gravel. Only I was in a parking lot the last two times. I had taken in the car to the dealership for the cruise control issue, but they could not re-create the problem. I live in Texas where you know it has had several 100 degree plus days and that is what we originally thought. But now this other issue is coming up? I am getting a little frustrated. How many others out there I wonder are having this type of issue????

 

No problem here! I've driven on the interstate and made cruise control my "must have". Heavy foot problems.

 

http://www.youtube.com/watch?v=_tHWFRRvRyo

 

Did you talk with the dealer about this yet?

 

you might have a brake switch (or clutch switch or other) problem

 

Maybe that was the toyota Hybrid sharing thing they were talking about?!?

 

Yep, and they could not recreate the problem. That is why I decided to video it and post for help.

 

If I were you, I wouldn't use the cruise control until they can determine the cause. Sounds like it's erring on the side of caution and disengaging because of the problem right now, but if the system is failing, you don't know what you're going to get. It could lock while it's on, and then you get to deal with what the OP experienced.

 

I just drove to colorado and back to vegas recently used cruise control 90% of the time. The only problems I noticed was it would randomly increase my speed by a few mph sometimes even going on flat roads.

 

another reason i'm not a huge fan of the electronic throttle, aka drive by wire. it could happen on a cable operated system sure, but its just one more nail in the coffin for the drive by wire in my book. i guess i'm stuck in the past..but the past is just as reliable imo..

at any rate, if the problem does persist and the dealer is able to find a fault with the system, please post back so the community can have a heads up as to what could cause the problem.

 

have any problems is because you did not have to shut it off in emergency mode.
I have had 2 close calls on mine, but I did have my feet out the window when I had to turn it off. Yeah, I know, who rides with his feet out the window!