exintake mod, high idle
#1
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I recently did the exintake mod on my ITB setup, and it runs great and I can definitely feel more power, but I've got idle issues now. the first few hours after I did the mod the car idled rock solid at 1krpm like usual (normal for ITB's) but now it won't idle under about 1400rpms. From what I understand, the normal way to adjust the idle is by adjusting screws on the throttle body, which I don't have. Is there something on the IAC i can mess with to adjust the air flow at idle, be it a screw or settings in megatune? I didn't want to mess with my frequency settings in megatune because I thought that messing those up could fry your IAC. thoughts?
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the irtbs throttle plates are all fully closed at idle. i have little silicone tubes that connect to each runner after the throttle bodies and they route back to a piece of aluminum that bolts to the stock IAC. so when it goes into idle mode, the stock iac opens, and the air gets routed into each runner individually via a little tube. shitty pic:
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#6
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well that might actually be the best solution, as my cam timing is now slightly advanced, which would explain the elevated idle. but can't you adjust the iac to not flow as much air at idle?
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Did you advance the intake cam? You want to retard it, not advance it. This will help you get the idle down a bit as well.
It's my understanding that when fully warmed up (on a motor without IRRRRTB's anyway) that the IAC valve is fully closed. So you can't make it any more closed than shut.
It's my understanding that when fully warmed up (on a motor without IRRRRTB's anyway) that the IAC valve is fully closed. So you can't make it any more closed than shut.
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