What is the timing advance on a 1993 Chevy Lumina?

You can't give a single number for timing advance on a 1993 Chevy Lumina. The timing advance is dynamic, meaning it changes constantly based on several factors controlled by the engine control module (ECM). These factors include:

* Engine speed (RPM): Higher RPMs generally require more advance.

* Engine load: Heavier loads may require less advance.

* Engine temperature: The ECM will adjust timing based on whether the engine is cold or at operating temperature.

* Sensor inputs: Various sensors (like the oxygen sensor, crankshaft position sensor, etc.) feed data to the ECM which informs timing adjustments.

There's no single "correct" timing advance value. To find out the *actual* timing advance at any given moment, you'd need a scan tool capable of reading live engine data from the ECM. Even then, you'd see the advance changing continuously.

If you're having issues with the engine's performance or are trying to troubleshoot a problem, it's not recommended to try adjusting the timing yourself on a 1993 Lumina. This is because it's controlled electronically and incorrect adjustment can cause serious damage. Use a qualified mechanic and/or a reputable diagnostic scan tool to diagnose and solve problems.