I would log RPM, fuel pressure, maf counts, fpdc, short term fuel trims, coolant temp, voltage. Maybe a few others I'm missing. You need to datalog while drive when everything is good till it goes bad. Note the time so you can corelate to the log. Post it up here afterwards.
Also FYI, when datalogging with the xcal2 your dash gauges will sometimes act funny and sweep or jump around. It's normal.
Also FYI, when datalogging with the xcal2 your dash gauges will sometimes act funny and sweep or jump around. It's normal.