I made a log of a standard, every-day drive to work this morning. No heavy acceleration or anything unusual, just a leisurely drive to work. Looking at the log, there seem to be a lot of significant and abrupt changes to cam position, spark timing, and throttle position with minimal change in accelerator pedal position or driving load. Let me say, i have not done any MAF or VE tuning YET.
The first thing that seems odd to me is this screenshot. Cam position goes to 0deg and throttle position spikes to compensate. Could this be indicating that 0deg is far from optimal on a power prospective? What about fuel economy? I thought retarding the cam reduced manifold vacuum, but this makes it appear as if advancing the cam reduces it. Is this just an illusion?
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The next thing that seems odd is this spike in throttle position and cam position. There is no change in accelerator pedal position, but the throttle, cam, and spark abruptly changed. Any thoughts what would cause this? It happens a few times during the drive.
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The last thing, for now, that I find odd is the throttle position abruptly changes with no change in pedal position or cam angle, just spark timing. The cam position changes shortly after.
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Are there more sensors involved here than just what I am looking at? Is this an indication that some tuning really needs to be done here? I tried attaching the log file, but I must be doing something wrong. I cannot get it to upload. Is there a size limit, its 10.1MB. I know its hard to say anything without it.