Is there a way to control idle speed?

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Why is idle speed control important in Haltech elite?

And particularly with idle tuning, this is one of those areas that I find is really important if we really want to replicate the sort of drivability of a factory car, and particularly for a road car, something that’s going to be road driven, this is always my aim.

What do you need to tune a SU carburetor?

Here we have a photo of my ancient PSW Tool, which is designed for tuning SU carburetors. It contains a pair of tubes and wires for balancing the carbs, a jet adjustment wrench, and a (completely useless) “jet centering” tool, which may be seen peeking out of the plastic pocket, just to the left of the jet adjustment wrench.

How does setting up timing affect idle speed?

Setting up your timing like this has a stabilizing effect on the idle. When the idle speed drops, the timing advances, increasing power and moving the idle speed back up. The result is an automatic feedback loop that helps maintain a constant idle speed.

Why does my MegaSquirt have an unstable idle speed?

If you’ve specified less timing below the target idle speed than you have at the idle speed, this often makes for an unstable idle as the ECU pulls timing while the idle speed falls. This can make a slight disturbance in idle RPM amplify itself into an idle speed that cycles up and down rapidly.

What’s the difference between MS1 and MS2 idle?

MS1 has a two point curve, while MS2 and later lets you set a more detailed curve of IAC valve versus temperature. Closed loop mode tries to maintain a target idle speed. While not every car needs closed loop idle, it can help compensate for major changes in load.

What should idle ratio be for batch fire engine?

So, if your engine is batch fire, you’ll need to add a little more fuel so all the cylinders can stay at 14.7:1 or richer. Batch fire engines typically idle best in the mid 13’s, so if you’re leaner than that, put in some more fuel and see if that stabilizes the idle. You’ll need to make sure the air/fuel ratio is maintained during cold start.

There are various schemes for operating a valve to introduce bypass air for idle control. One relatively common method for controlling the idle speed bypass air uses a special type of motor called a stepper motor.

Who is the inventor of idle speed control?

A highly simplified two-input (idle bypass valve opening and spark advance), two-output (engine speed and intake manifold pressure) idle speed control model for IC engines was developed by Yurkovich and Simpson (1997) and used in this work.

What happens when you idle the air control valve?

Normally, if you just start your car, the idle air control valve will cause the engine rpms to increase and slowly decrease. That would be a sign that your IAC is working.

How can I tell if my idle control motor is working?

Look for a difference in idle speed. Allow the engine to run for a minute so it settles to a consistent idle, then take note of any difference in the idle RPMs versus the idle you observed earlier. If the idle has not changed at all, it’s likely because your idle control motor has not been functioning.

Can a faulty idle air control cause a problem?

A faulty idle air control (IAC) valve can cause a number of problems with your vehicle: 1. Incorrect idle speed: An IAC valve that sticks in the closed position will create an idle speed that’s too low.

Where is the idle air control valve located?

The valve is a major management component of the engine which will either decrease or increase the number of revolutions per minute, depending on what the current operating conditions call for. The valve is connected to the throttle body next to the intake manifold.

Is there a way to control idle speed?