Engine not running right
 

Hi i have a 2005 with 24000 KM (15000miles) with engine running a bit "off" lately. ive had regular maintenance done to it and it only has a aftermarket air filter done to it. ive never flooded it and i always drive it hard.

so this is the story. its a week now that the engine is ruff to start, it hesitates almost chokes and then starts. the engine still runs but feels weaker more like 80% capacity. gas milage is bad, and sound of engine isnt smooth, sounds a bit grindy instead of the clear whining sound when i push it hard.

I took it in today to get checked, the stealership said my plugs were dirty and were misfiring. those pricks changed them and then said everything was perfect, but the car is exactly the same as before i took it in. i searched a lot on the forum and im still not sure whats next that could be the problem... coils, bad cat? anyone have any ideas? im going to bring the car in again on monday since nothing got resolved, just emptyed my wallet for nothing and pissed me off. anyways let me know your ideas. thanks

It could be coils, wires, dirty MAF sensor, cat, you might make sure you have the new style starter it was changed in 2005. You should check your battery and terminals that could be your slow starting. What were your charges? Spark plugs are about $80(US) wires are about $50 and coils run around $30 each and all take about an hour with a buddy to change.

First of all it might be better to post your thread under the Trouble shooting section.

I assume your rx8 is manual, right? Do you get any CEL? If your car was misfiring you should get intermittent CEL. To check your cat just drive it until it gets warmed up (push the car a bit if this is possible) and then check your cat underneath the car. If the cat is clogged it should glow red. Further, you might want to stick your nose at the exhaust (not too close and not for too much time) and see if you can smell anything funny (besides gas). If cat is bad the smell should be kind of bad. Another symptom of bad cat is some rattling noise.

What kind of air filter you have? If it is an oil filter and not dry you might want to check your MAF and clean it if it is dirty.

Coils

Coils and a good sea foam.

UPDATE: the stealership just called and said the coils need to be changed. but these idiots couldnt see that when they changed the plugs. anyways, it will be ready next week. thanks for the comments

matt do u pay for this?how much u have to pay? or your warranty pay for it ? cause my 8 still under warranty