Hi rx8 experts,

I know rough idling is a well discussed topic here in the forums and believe me, I've searched and not found a possible solution yet, and i'm not sure I've come across a similar situation.

Ok so basically with idling. First things first, motor mounts. So i popped the hood and kept the engine on.. there was absolutely no vibration coming from the renesis engine and the motor mounts, I placed my hand in the mount and the engine for more than five minutes, no vibrations.

Does that rule out spark plugs, coils and motor mounts?

Let me further describe the vibrations..

1)It's sort of cyclic, coming once every 5 seconds when idling. It's not too serious, but i'm just status it might escalate.

2) there's a low humming sound on top of the amazing whirling sound of the rotary engine. When I step on the gas, the low humming gets louder.

3) sometimes when moving from a stand still, when I put too little gas through, there is a g huge vibration and loud rattling sound coming from under the hood.

I'm guessing the problem is something below where the engine is mounted, and I can't see it.

Please help me.

By the way, I have no experience in diy, and i have very very little knowledge about these technical stuff

 

Blown motor mount?

 

Thanks stealth tl, but won't I be able to see and feel the vibrations on the mounts when I open the hood? The mounts are very easily accessible and visible. Am I missing something?

 

i bought a 96,000mile car, that had not had the mounts replaced, so i was expecting them to be bad. i looked for bulletins and the motor mount diagnosis is to be decelerating in 3rd, @3000rpm and hit the gas, if the car hesitates, the mounts are bad.

i think the factory installed (up to 2007?) mounts are liquid filled, so they can also leak. they updated to normal rubber, and if you have a car with the liquid/early mounts they are suspect, and you should plan on changing them anyways.

if you're sure the vibration isn't the engine, there really isn't much else it could be

good luck!
mike