Very Rough Idle!!!!
 

Here is the story, I will try to explain it as best as I can:

I live in MD and we just had a MASSIVE amount of snowfall. After the first big snowstorm hit, our streets were very slick and not very driveable with my 8. However, I thought I would try to drive through it anyway because I needed to get to work. Sadly to say, I got my 8 stuck in the snow. After about 20-30 minutes of trying to get my car out, it just shut off completely. I am guessing it overheating or something, not really sure. So I waited for it to cool off and eventually got it back home in a parking spot.

So today, 4 days later, I cleaned my 8 off after the second snowstorm and went to drive it, but it is not driving as it was before what happened above. Every time I put my brakes on and it gets down to a speed between 15-0 MPH, it begins to idle VERY ROUGHLY, and looks like it is going to drop below 500 RPMs, but the goes back up to around 600-650 RPM. This is worrying me very badly because I commute to school during the week and it feels like it is ready to stall out.

Can anyone figure out why this is doing this? I just recently had my Spark Plugs/Coils/Wires replaced and Zoom-Zoom Carbon Engine cleaner ran through my car as well. Everytime I turn my car off, I need to wait AT LEAST 30 minutes before I can start it up again, and it takes 3-4 seconds for it to turn over. My idle has always been rough, but now it is getting really bad. Also, anytime I run the heat/AC my idle gets rough to the point where everytime I stop I turn my AC/Heat off. Also when I have my lights on my idle is rougher than when I do not have my lights on. My Car Is a 2004 Automatic. It has around 38,000 miles on it. I drive it like it should be, redline it once or twice every two days or so, let it warm up before driving it. The only mods on it right now are the Typhoon Intake and Racing Beat exhaust which were on the car when I purchased it.

Any help is greatly appreciated!

P.S. - Ever since I bought this car in August, it has almost been nothing but a pain in the butt. It is getting to the point where, even though it is a fun car to drive and get plenty of looks which I love, I don't want to drive it in worries of something else is going to happen. I am starting to contemplate getting rid of it, but I am still torn and not sure what to do. I am a college student, and I need to worry about schoolwork and classes, not my car every single day. Any suggestions?

You forgot the basics: model year, manual or automatic, miles, any mods, driving style. Please provide these and I am sure that the rotary scientists will be able to solve your problems.

There you go I just put it in my first post.

I'm leaning towards battery or alternator.
And this is why:
More load (electrically) is causing your car to run rougher.
What brand battery do you have?

I have the one that was on the car when I originally bought it, I think it is Bosch or something.

But I haven't had this bad of an idle before and I have had the same Battery.

Honestly if it were my car, I would look at getting a new battery.
Especially with you saying more electrical load causes the car to run rough AND you have trouble starting (though if you still have the original starter, that can be the issue with starting too).
Some people will tell you the battery is not in use once the car is running... not true.
The battery acts as a regulator to keep voltage as close to 12V as possible.
This is especially helpful as you increase RPM, the alternator is going to produce more current.
So the battery can still be an issue even while driving.

Would that help with my idleng issue?

Possibly... because your spark plugs also need electricity.
So if you are losing current to other devices (like the headlights) you are limiting the "spark" to the spark plugs.

Yeah but that is the least of my worries right now. My idleing/almos stalling out issue is my big issue.

Do you have any local RX8 buddies you can swap batteries with to see if that helps?

Ummm... I'm telling they could be the same...

No :(

I just want a new Engine altogether!

Take it in for a compression test if you want a new engine... you might get lucky

It is just starting to annoy me how everytime I go in for a repair it runs good for 1-2 weeks and then something else goes wrong. How much do compression test?

I believe a compression test runs $90-$100, but the dealer should reimburse you if the engine fails.

How would I know if they would just say the compression test passed so they wouldn't have to worrying about a new engine?

They can give you a printout with the compression numbers.
Then we can tell you if they are good or not.

I will think about getting that. I am just sick of paying for repairs because the previous owner probably didn't take care of it very well. That is why I am thinking about a new engine, because then I KNOW that I am taking care of it well.

well you have an '04... lots of issues with that model.
I'm the original owner of my '04 so I've been through it too.
The batteries sucked... the starter was weak... so you need to make sure everything else is also "current" or else a new engine isn't going to help.
Though... a new engine is always nice to have, especially if you have an '04.

But in my mind I feel like by the time I make all of those repairs I will spend enough to pay for a new Engine lol.

I am just at a crossroads right now lol.

Get rid of that Typhoon intake.

Its a piece of shit.

Causinging idling problems.

Well I have had it since I bought the car and haven't had problems like this though.

I have to agree with Razz.
I had a local that had issues with his Typhoon intake.
I installed his stock intake and it ran better.
Those intake are known to have problems.

Well how much for a new stock intake?

You can buy them used in the Buy/Sell section of this forum.
Or go with an aftermarket intake like AEM/MazdaSpeed.
Even though it'll be good to get rid of that intake, and it has been known to cause idling problems, I still don't think that is causing your issues based on what you described.