Cold start RPM

Hello guys. So I have an issue with a cold start and finial RPM. SR20DET engine (fast idle cam is removed). At cold and ISC solenoid duty 100% I can't reach even 1000 RPM. Wile engine warms up the idle speed increases. When the engine is hot and I manually set the solenoid duty to 100% Engine speed goes easily to 1600-1700 rpm. So I assume that because of a cold engine it needs a way more air than a hot engine. Am I correct? Or simply I have a solenoid that malfunctions wile it is cold.

Can you manually adjust the main throttle stop ? If so open it up a little more to let some more air in at cold start . You may need to readjust your ISC numbers after doing this and re calibrate the TP sensor .

Yes, I can. So am I right? When engine is cold it needs much more air rather than when hot?

Yip - More fuel and a bit more air .

Thanks. Will do the test again. Only one attempt per day ))

Have you removed the coolant lines, that support the throttle body stop? I've seen the exact same happening on an SR before. Basically the ISC wasn't able to bypass enough air when the engine was cold.