I used a engine monitoring tool (e.g. Diacom, Auto-Xray, or Tech 1) on my engine and see retard as I floor it, no matter what octane I use. Is there something wrong with my engine?
Probably not: it could be because of emissions. Many cars retard the timing on take-off (slightly retard and *then* advance) to reduce the emissions. If you have a scan tool that can handle it, check the parameter “KNOCK SENSOR” in the PCM. It’s a numeric counter that records the number of knocks that the knock sensor has detected. If you have the capability of data capture on your tool, do a run and look at the KNOCK SENSOR parameter over the time course of a perceived knock condition. That should tell you if the retard is actually due to “real knocks” or some other reason. If it increased, your knocking. If not, you have something else going on. BTW, the parameter “KNOCK RETARD” will tell you how many degrees off of the optimum timing the PCM has retarded your timing to counteract a detected knock condition. If you know that your knock sensor is firing off without the engine knocking, then you can “desensitize” it electronically.
