* Engine Load: The computer adjusts timing based on how hard the engine is working. More load often means slightly less advance.
* Engine Speed: Timing will change with RPM.
* Engine Temperature: The computer will adjust timing based on the engine's temperature to ensure optimal combustion.
* Sensor Inputs: Various sensors (e.g., oxygen sensor, knock sensor) provide feedback to the PCM, influencing timing adjustments.
You cannot simply set a static timing value like you would on older, non-computer-controlled engines. Attempting to do so could severely damage the engine.
Instead of looking for a timing number, you should focus on:
* Checking for Diagnostic Trouble Codes (DTCs): Use an OBD-II scanner to check for any codes stored in the PCM. These codes may indicate problems with sensors or other components affecting ignition timing.
* Ensuring the Distributor (if applicable): While the 1998 5.7L likely uses an electronically controlled system, if you have a distributor, check for proper distributor cap, rotor, and ignition coil function, all of which will affect the timing indirectly.
* Professional Diagnosis: If you are experiencing performance problems (poor acceleration, misfires, rough running), take the vehicle to a qualified mechanic for diagnosis. They have the tools and expertise to properly diagnose timing-related issues.
In short, trying to find a "timing degree" for this engine is the wrong approach. Focus on proper functioning of the entire engine management system.
