How do you set the ignition timing on a 1995 Mustang GT?

You can't adjust the ignition timing on a 1995 Mustang GT in the same way you would on a carburetor-equipped car. The 1995 Mustang GT has a computer-controlled ignition system. The ignition timing is managed by the Powertrain Control Module (PCM), also known as the Engine Control Unit (ECU). There's no distributor with a mechanical advance to adjust.

Attempts to manually adjust the timing will likely damage the engine or the PCM. The PCM constantly monitors various engine sensors (like crankshaft position, throttle position, etc.) and adjusts the timing accordingly for optimal performance and emissions.

If you're experiencing problems related to ignition timing (like poor performance, misfires, etc.), you should NOT try to adjust it manually. Instead, you should:

1. Diagnose the problem: Use an OBD-II scanner to read trouble codes from the PCM. This will pinpoint the likely cause of the issue. Common problems can include faulty sensors (crankshaft position sensor, camshaft position sensor, etc.), a failing ignition module, or even a bad coil pack.

2. Consult a repair manual: A Haynes or Chilton manual specific to your 1995 Mustang GT will provide detailed information on diagnosing and troubleshooting engine problems.

3. Take it to a mechanic: A qualified mechanic with experience in OBD-II diagnostics and Ford vehicles can accurately diagnose and repair the problem. Attempting to adjust the timing yourself without the proper equipment and knowledge is highly discouraged.

In short, don't try to adjust the ignition timing. Focus on diagnosing and fixing the underlying problem causing the symptoms.