My RX-8 is now having an RPM problem when you first start the car before it warms up. When I first start it and let out the clutch to let the car warm up it keeps jumping from 2k RPM to 1k RPM till the car gets completely warmed up and im not sure whats causing it. Any ideas?

 

Peek at some of the suggestions in: Replacement engine stalls at idle? https://www.rx8club.com/series-i-trouble-shooting-95/replacement-engine-stalls-idle-218004/

 

it could be normal.
Are you getting any other signs of issues?

 

neutral gear sensor is the first thing that comes to mind. It usually will give a cel though I thought. Mine is bad right now and does the same thing.

 

http://www.youtube.com/watch?v=tEA8ZRM7bJk

Here is a video to show you just exactly what happens. Thought it would help more than just trying to explain.

 

Exactly what mine did at first with it's replacement engine, except mine would stall after a minute or so of that.

My receipt says that Mazda then cleaned the injectors, throttle body, air intake system and intake valves... and the problem went away.

 

This same exact thing is happening to me.
When I press the clutch in, it idles perfectly, but when i let out in neutral, it idles at like 1350 and jumps between 2000 and 1000.
Did you find the solution to this? The dealer told me "you need a new throttle body and a new clutch switch" $800 dollar job. I said no thanks and took my car out.

Any ideas??

Thanks guys

 

Mine was an easy fix. I found that if I only use premium NON ETHANOL gas it stoped having the idle problem.