Originally Posted by
blindsquirrel
Mass Airflow of 8.5 g/s on a 5.3L that idles at ~35KPA, that's not right. If the MAF is reporting it's using a lot more air than it really is, and the ECM adds fuel to suit, but the O2s say 'whoa dude, that's rich!' the trims will pull more and more fuel until it runs out of adjustment.
Do the trims start to head back down if you hold it at a steady ~2000 RPM?
No tune file, no vehicle info or description of what's done to it, not nearly enough channels logged, no logs while driving, not even anything that's non-idle in park. That makes it really hard to say anything more.