If your Sebring's idle is too high or too low, the problem lies elsewhere. Possible causes include:
* Dirty or faulty throttle body: A build-up of grime can interfere with the throttle plate's operation. Cleaning the throttle body is often the first step in troubleshooting idle issues.
* Vacuum leaks: Leaks in the intake manifold or vacuum lines can disrupt the engine's air-fuel mixture, affecting the idle.
* Faulty idle air control (IAC) valve: This valve regulates air intake at idle. A malfunctioning IAC valve is a common cause of idle problems.
* Mass airflow sensor (MAF) issues: A dirty or faulty MAF sensor can provide inaccurate readings to the PCM, causing incorrect fuel delivery and affecting idle.
* Problems with the PCM itself: While less common, a malfunctioning PCM can cause a variety of engine problems, including idle issues.
* Dirty or clogged fuel injectors: This can lead to inconsistent fuel delivery affecting the idle.
Instead of trying to adjust the idle yourself, you should:
1. Check the engine for trouble codes: Use an OBD-II scanner to read any diagnostic trouble codes (DTCs) stored in the PCM. These codes can pinpoint the source of the problem. Auto parts stores often offer free code reading services.
2. Clean the throttle body: This is a relatively easy DIY task, and often solves idle problems. There are many videos online demonstrating this procedure.
3. Inspect vacuum lines: Look for cracks, holes, or loose connections in the vacuum lines.
4. Consult a repair manual: A repair manual specific to your 2001 Chrysler Sebring convertible will provide detailed information on troubleshooting and repairing idle problems.
5. Take it to a qualified mechanic: If you're not comfortable performing these tasks yourself, or if the problem persists after troubleshooting, take your car to a qualified mechanic for diagnosis and repair.
Attempting to manually adjust the idle on a modern electronic fuel-injected engine is strongly discouraged. It's much safer and more effective to diagnose and fix the underlying problem.