What are the symptoms of a bad idle control?
Usually a bad or failing idle control valve will produce a few symptoms that can alert the driver of a potential issue.
- Irregular idle speed. One of the most common symptoms associated with a problematic idle air control valve is irregular idle speed.
- Check Engine Light comes on.
- Engine stalling.
How does open loop idle control work on an ECU?
Secondly, as the engine heats up, adjust the base idle effort in the base duty cycle table against coolant temperature. Extrapolate past the ends as needed. The other way to do this is to enable closed loop idle control, and then allow the closed loop function to settle on the target idle speed.
How does the idle speed control system work?
Idle speed control system. In addition, the digital engine control system receives digital on/off status inputs from several power-consuming devices attached to the engine, such as the air-conditioner clutch switch, park-neutral switch, and the battery charge indicator. These inputs indicate the load that is applied to the engine during idle.
What should I do if my idle control motor is disconnected?
The engine should still start and run without any issue despite the idle control motor being disconnected. Be sure to tuck the wiring you disconnected up in the engine bay so it doesn’t get caught in any moving parts. Look for a difference in idle speed.
How can I tell if my idle control valve is working?
To check if an idle control valve is working properly, start by turning on your engine and letting it run for a minute or 2. Then, when it’s at an idling speed, take note of the RPMs in your car. Next, turn the engine off and disconnect the idle control motor under your hood.
How does the ECU control the idle speed?
As you may guess the higher the position the higher the air bypass, thus the higher the idle speed RPM. The ECU controls the idle air control valve by supplying battery voltage to either of its two internal motor windings, one of them extends the pintle, the other retracts it.
How does the idle speed control valve work?
Controlling the idle speed is a dynamic process, the ECU is constantly adjusting it depending on engine conditions, for example, each time the A/C compressor turns on the ECU opens the air bypass to prevent an RPM drop. How do you diagnose a failing Idle Air Control Valve?
How to set up idle control on modular ECUs?
Copy the final idle effort into the table at each temperature cell as it is reached. Next, you should set up the idle-up for loads.
The engine should still start and run without any issue despite the idle control motor being disconnected. Be sure to tuck the wiring you disconnected up in the engine bay so it doesn’t get caught in any moving parts. Look for a difference in idle speed.