Hey, 2008 Escalade with just over 200k miles has very low power especially at low RPM and misfires as it gets hotter. At 70s outside it's not that noticeable but we just took a trip where it got over 100 and the power sag and misfires were very noticeable.
I have changed the plugs and wires within the ladt 30 to 40k but it seems like maybe an electronic like an ignition coil or something but of course there are no codes. Any thoughts?
Does your scan tool show live data? You need to see what the sensors are reporting. If they're reporting erroneously, but within spec, there won't be any codes but the PCM will adjust fueling and timing based on the erroneous reporting. For example, let's say your Intake Air Temp (IAT) sensor is reporting the temperature to be 180° (arbitrary figure). Although it's actually not 180°, the PCM sees this as "possible" (within range) so it just does as it's programmed to do and makes adjustments accordingly. One such adjustment would be to significantly retard the timing which would surely result in a loss of power.
Also, does your Escalade have the 6.2 with VVT? There's an issue with the cam phaser hanging up or something like that where it has the cam at the wrong advance or retard.
See if your scan tool shows live data, misfire counts, etc. As was mentioned about the market of counterfeit plugs, checking the plugs, or a few random ones would be a start.
