i'm running the TEC2 on a EJ20TT (SUBARU 2.0L TWIN TURBO JDM). I'm having truble with the idle ever since i bought the rail. after getting the engine started and runns for a few mins the idle will start to jump (i guess) falling the climbing and falling and climbing and ... then it dies. any idea what this could be caused by?

thanks for any help

I'd bet your minimum on-time is too low. Once the engine warms up, the injector pulsewidth is getting small enough that they start to fail to open all the way. The lean condition causes the engine to stumble whcih causes the Idle motor to crank open to prevent the stall which raises the manifold pressure which increases the pulsewidth to the point where the engine revs up which cause the IAC to crank shut again which causes the loop to start again.

Short answer, raise your minimum on-time or richen up idle in the VE table.

Cool, thanks for the explanation, and the short answer. that's what i was starting to think. i think i'm starting to get a grasp on this whole thing. after readind almost every article in here. thanks again.