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Initial startup

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I have an 04 cobra and when it starts up from an initial cold start up it does fine and then hits a rough spot maybe a minute or two later and then smooths out. What should I adjust in my megasquirt to correct this?

It's likely this is some compensation or reaction to a change in operating conditions?

Is there a compensation that ends around that time? Does this time represent the delay before closed loop is enabled?

What is happening to the mixture (Lambda values) before during and after this 'rough spot'? Does your engine have an idle air valve? What is happening with that?

What happens to the battery voltage? Is the battery being charged (alternator providing current) while warming up (some alternator setups don't run until the engine speed exceeds a threshold like 2000 RPM).

What is happening with the engine coolant? Could this be when the thermostat first opens and then engine cools down and needs more fuel?

What is happening with the air temp? Does it suddenly change?

I have an idle air control valve, the fuel mixture is rich. The battery voltage is around 13 volts or higher. The thermostat isn't opening until about 190 degrees. I havent checked when the alternator kicks in. I have to check the idle air control valve tommorrow morning to see what its doing exactly at that time.