Ok, so I bought an 04 rx8 about 2 months ago and it has recently started idling pretty rough. Occasionally it will shut off, but then it will start again and run fine, anybody have any similar problems?

 

is it auto ? because this happened to me before and i got a new engine..if not, new motor mounts/coils/spark plugs/battery?

 

Do you ever receive a CEL?
Could be coils, ignition wires, or spark plugs.
Spark plugs are usually the first thing you try.

 

kind of similar.

my 8 had a moderate rough idle, right after i noticed that, i noticed a weird buzzing/fluttering noise from 4-7k during hard acceleration. I changed the plugs, no effect then i changed the plug wires and coil packs at the same time, and it was fine after that. so i'm assuming a misfire? it never threw a CEL. i'm no mechanic...but it runs a lot better and gets about another 30 miles to a tank (250 +/-). ended up costing about $260 from atkins rotary. check their site for the pricing. it can be done with basic hand tools but you will need an extension. if you're in the greater seattle area, they're in puyallup.

good luck

 

idk what a CEL is... i had flooded the engine earlier and the dealer said that spark plugs were good... it is an automatic though... so i need a new engine?

 

CEL = Check Engine Light.
I wonder if the dealer really checked the plugs.
Flooding tends to foul the spark plugs.
I wouldn't suspect bad engine right away, eliminate the little things first.

 

do a compression test..does your engine make weird sounds? like a tick tick tick sound?

 

had a cel once, put a new gas cap on it and it went away.... tiny leak they said, but everything was fine. no tick tick sounds btw