Send back that short ram.  Won't do you any good - best to spend the money on up-pipe, down-pipe, or exhaust.  The car gets plenty of air, it's the stuff around the turbo and the exhaust that holds it back.

Always, always, always go after the simplest solutions FIRST.  9 times out of 10, it's something simple - and you'll keep yourself from tossing money at the thing unnecessarily.  Be patient.

Fuel, Air, Spark.

Before you do ANYTHING ELSE - go find an Autozone and plug in an OBD2 scanner.  Pull your code, that'll tell you if the ECU detects an actual misfire.  If you're not getting lights on the dash and you can't get a code, then chances are it isn't the Spark that's giving you problems.  Might be a good time to take that refund on the Cobb short ram and spend it on a scanner for yourself.  It will more than pay for itself over the next few years.

Pull the plugs, inspect the porcelain insulators for cracks.  Re-gap to the middle of the recommended range, reinstall.  You shouldn't need a torque wrench - I've done plenty of plug changes without one and never a problem.  Just don't get all Conan on the thing.  I've also found that a little bit of Anti-seize on the threads does wonders, 30k down the road when you go to change them.

That's the simplest check, first.  If that doesn't solve it, then try and trace the misfire by wetting down the individual wires with a spray bottle and water.  If it stumbles when you wet one of the wires, then there you go.

Wires and coil pack are integrated, IIRC.  So you'd have to change it all at that point.

Then you'll want to figure out if you're getting a leak in vacuum or if the intake system needs looking at; the Air problem.  I'm pretty sure it isn't a fuel issue if you ran a Techron or SeaFoam through the tank a couple of times.  Could be there's some gunk in the system somewhere, but if you've been running premium and don't have issues anywhere else in the RPM band, chances are the problem is around the injectors, which gets you into that 1 time out of 10 that something ISN'T so simple.  That's about when I'd double check all the easy stuff first to make sure I didn't miss something.

Last edited by Bryan (2012-04-25 19:34:13)

Not sure if I missed this while reading...but have you verified that it's actually a misfire with a CEL and code, or is it just that you can feel a stutter?  Have you reflashed the ECU, or is it stock?  The stock tune on these cars will cause the car to stutter under full throttle around where you are saying (not misfire, it's just a stutter).  It happens because the engine is switching between closed loop fueling and open loop fueling...if you're wanting to learn more about these cars, this would be a good thing to read up on.

As for the spark plugs...I will be impressed if you get a torque wrench on the plugs.  Here's what I do...screw the spark plug by hand until you feel when the crush washer first makes contact, then tighten some more with a wrench, and you'll feel when the washer is completely crushed because it'll get a lot harder to turn.  Get it to that point, then snug it up a hair more.  Unless the spark plug is way loose and on it's way completely back out of the cylinder, this probably isn't your issue.

Oh, and the idle is relatively rough in these cars.  Just the way they are.

Last edited by kornfeld (2012-04-25 20:20:29)

I changed the plugs to begin with to attack the problem.

No CEL and havn't plugged it in, stock ECU.  I plan to keep the intake, it has good reviews and i plan to do A LOT to this car, so that short ram isnt going to hurt, but yes I know they aren't meant to add power on these cars.. $150 isnt killing me.

No I have not cleaned the MAF

I CAN get new coils for $160..

So, start with taking them all back out and replacing them? Clean the MAF? And...what else?  What supporting mods are going to possibly help this the most? I have the money and was planing to order a uppipe and downpipe next. Wait to see how they affect it?

I appreciate all responses and im still learning so thanks for the help, as for the idle, thats what i thought too my other subie was the same way..

Im going to clean the MAF tonight and put the ram in, plan to order down and uppipe this weekend.  Ive been learning a ton and I really love it. We will see how this goes, might reset the plugs this weekend too. I always run 91 or 93, 93 currently in the car (only one 93 station on the area)

Here's a great place to start:

http://forums.nasioc.com/forums/showthread.php?t=533787

I've go sure money on CEL P0171 after intake is installed. 

You're on. Worth a buck. 

Time frame: CEL >1 month after install work for you?

If you meant <1 month, then yes.

Good catch. Almost had you nailed for a no risk bet.

Sounds like he's running Mobil 1 to me.