It still breaks up once in a while but nothing like it used to. I don't remember the brand but it was one of the ones you just dump in the tank.

edit: I should also add that I don't have any issues while daily driving or under WOT.

 

Sounds like your Idle Air Control/ IACV is acting up or a possible MAF sensor. You could try cleaning your MAF sensor with MAF cleaner (bottle just like carb cleaner but made just for MAF sensors). Be careful though, it's sensitive.

You'll most likely need to replace/fix your IACV or MAF sensor.

 

Yeah I've thought about both of these things but I've gotten tired of buying parts that don't fix the problem. It's running OK for now so I'm probably going to wait until it gets worse before I worry about it again.

 

hmmm...
what i would suggest is a few things but i'm sure you already hit 95% of them
-Check your Front 02 Sensor (from the 02 housing all the way up to the connector
-see if you could replace the stock injectors with some New OE injectors
-pour 3/4 of seafoam into your tank and let it sit for a while. Then pour 1/2 of seafoam into your brake booster vacuum line that runs to your head...(While running) slowly, then pour the last bit in fast enough to where it stalls your engine then wait about 8-10 mins before starting your car
-check your entire exhaust from ext turbo-to-02 housing-to-downpipe-to-cat/test/straight pipe for any leaks
-*IMPORTANT* inspect your ignition coils and BOOT especially to be sure that the metal connectors aren't broken or cracked.

but from what all i've read you seem to be thoroughly inspected, i know it gets frustrating because i've been down that looooong road before.

 

Was this issue ever solved?
Having similar misfires on my X. And yes I know it all different.
But I'm running on my 3 year now.. I'll try anything!
My misfires goes away as soon as I put any load on engine, like turning ac on or similar.

 

Sorry I never updated the thread. I did end up solving the issue by replacing the MAF sensor believe it or not. As far as your X goes. One thing I ran into recently when tuning a X for a local guy is that he had values in the mid 20s in the idle range of his timing map and he was also experiencing a slight misfire at idle. I lowered the timing down to around 10 in that area and the misfire completely went away. Might be worth looking at the tune before you start changing a bunch of parts.