So Blaze the Wondercar II is a 2001 LT 4x4 with 119k mi. She has recently developed an increasingly common intermittent hard miss / stall until warmed up. Once warm, no problem at all.
The issue seems to be ignition related with power dropping out completely for up to seconds at a time. The tach drops to 0 then recovers, or stalls completely. When this happens it'll run very rough under heavy throttle & smells rich but throws no code.
Any recommendations for a scan tool that I can gleen live data when this problem happens?

 

Scanners:

https://blazerforum.com/forum/2nd-ge...lazers-103424/

Once you get set up with live data we need to look at your sensor values and fuel trims. My guess is a bad sensor which corrupts initial fuel delivery which gets corrected at closed loop by the O2 sensors. In the meantime you should check fuel pressure leak down when it runs like crap. Normally heat makes electronics fail not heal but it can happen.

George