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high and unstable idle

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i'm fairly new to tuning and i can not figure this out.

i have been trying to get a stable idle for over a month now, but after reading ALOT of forums and doing the hpa courses i'm still having the same problem.

i'm truly at a loss and i would really appreciate if someone could help me out.

i have a 99 mazda mx5/miata with the 1.6 nb engine.

current tune: https://drive.google.com/file/d/1hP9ThM4jClL0IRBpyWyIipsuFTzEXiUC/view?usp=sharing

datalog: https://drive.google.com/file/d/13KQfDv1iyHkZoUOW5WkU2Gv5lw2-4mND/view?usp=sharing

Things that lower the engine torque (and thus idle speed):

- Reduced airflow (ie, close the throttle more)

- Retarted Ignition (reducing timing in the area around and above the target idle, will slow the engine into the idle range.

With this information in mind:

- Have you checked for vacuum leaks (includes stuck / backwards PCV valve, stuck EGR mechanism, leaking manifolds, cracked vacuum hoses)?

- Have you verified the ignition timing with a timing light.

- Some other mechanical problem like: cam skipped timing and is running advanced, or sticky throttle linkage that doesn't return to the stop, worn throttle shaft.

Sticking brake booster/servo check valve can also cause issues.

We usually reply within 12hrs (often sooner)

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