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I did my transmission swap a while back. Ever since i switched to mannual ecu, the rpm will stick at around 2000 rpm(or even higher) and then drop back down to 700 after couple seconds. The car ran fine tho. No stalling issue. Now, I just put my turbo on last week. For some reasons, the car will stall whenever i pull the gear out to natural. I have to leave the gear in as long as possible before the car stop in order to not let it stall. I still have auto iac valve on and was wondering if I change it to mannual iac will solve it.