the rev go unstable after the engine is warm
 

hi everybody my rx8 the rev it goes unstable when the engine is warm, it happen when i stop the car and i can feel the car is shaking when i was in the car,
will that be the air fuel ratio problem becox i had changed the air filter and muffler?
do i need a air fuel controller? or should i go ask the car dealer to reset the ECU?

What does your TAC show?

Mine has that problem when the A/C clutch engages. The RPMs drop slightly, but the whole car shakes. If the passenger-side back door is open, it sounds like it'll rattle off the hinges. I'm going to try (yet again) to get the dealership to figure it out. Actually, I'll be trying another service department this time.

my tac show rev in 800 and then it drop to 600 and then goes up again~
and my oil pressure guage it shows unstble goes up and down as well

You can reset the ECU yourself. Do a search and you will find out how.

Welcome to the cult.

ive ask the machanic abt it and he said becox i was using the cyctheic engine oil~ and i should use the mineral engine oil~ what a big mistake for me~
so do u guys think this is a big problem?

The USA oil pressure gauge is an idiot light. ( It stays in one position unless you lose oil pressure completly.) After warm up your TAC should stay at 800 unless your AC is going on and off. If it is still under warranty I would take it to the dealer, but it is not a big problem IMHO.

I have that problem aswell, it feels like the car is goin to stall. And ive only done 500 miles in my rx8 and havent changed anything.

If this car is still under warranty, take it back to the dealer and have him check it out. Otherwise, look around in the engine compartment for a vacuum hose that has become disconnected.

hmm the last time i had a problem like that was my sparks or my fuel injectors. well that was with my 4 banger of course and i have no idea what with the rotary but hope that helps.

wow i feel soooo relieved, after my tranny broke on me im not confident nor confortable in my car, its gonna take time to heal.... so i used to look for any lil thing to think the car messin up.