Idle is dog shit and probably my tune also.
Hello first time in these forums. Have a 92 Miata that idles around 1400 rpm When warm. Also start up is a little rough. Also the idle adjustment screw is almost maxed out.
Car is making 8lbs. Have all sensors needed and have 450cc injectors. If anyone could look over my datalog that'd be amazing. If you need the tune file I can send that too. Any help is greatly appreciated. Thank you. Attached the tune as well
Car is making 8lbs. Have all sensors needed and have 450cc injectors. If anyone could look over my datalog that'd be amazing. If you need the tune file I can send that too. Any help is greatly appreciated. Thank you. Attached the tune as well
Last edited by Julian; Oct 10, 2025 at 05:39 PM.
Your idle control is currently set to "off", so it's not doing anything. Make sure there's no leaks in the intake system, then try the below tune. It's not going to be great, but it's a start. The valve, if functional and wired, should try to control idle. Once warmed and idling, look at "PWM idle duty", and turn your idle adjustment screw clockwise until idle is sitting at 950rpm. Wait 30-60 seconds between adjustments. Go big at first with the screw, 360+ degrees, eventually smaller changes like 90*.
I didn't look at the rest of the tune, so if this works, it'll still need fine tuning.
I didn't look at the rest of the tune, so if this works, it'll still need fine tuning.
Your idle control is currently set to "off", so it's not doing anything. Make sure there's no leaks in the intake system, then try the below tune. It's not going to be great, but it's a start. The valve, if functional and wired, should try to control idle. Once warmed and idling, look at "PWM idle duty", and turn your idle adjustment screw clockwise until idle is sitting at 950rpm. Wait 30-60 seconds between adjustments. Go big at first with the screw, 360+ degrees, eventually smaller changes like 90*.
I didn't look at the rest of the tune, so if this works, it'll still need fine tuning.
I didn't look at the rest of the tune, so if this works, it'll still need fine tuning.
Thank you for the response. Definitely will try that out. Could these be the reason why? Have new ones orders now.
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