BlueCollarTahoe
Full Access Member
- Joined
- Sep 21, 2016
- Posts
- 553
- Reaction score
- 120
bump
Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.
Can you graph data? Specifically B1S1 B1S2 B2S1 and B2S2. Monitor these 4 at OT in park at 2k rpm. No accessories on and turn all the lights off.
Can you graph data? Specifically B1S1 B1S2 B2S1 and B2S2. Monitor these 4 at OT in park at 2k rpm. No accessories on and turn all the lights off.

It's your cats. Those lower O2 sensors should be moving around like the upper ones.
You're right, my mistake in that the lines from both the upstream and downstream look similar only while cold, not hot. Your bank 1 is more normal than bank 2 lower sensor, they should both respond to rpm changes.
Is the 93419 the whole enchilada, cats and y-pipe? I installed basically the same thing on mine in February, 51578 for GMT900, and it's working great and my mileage came back after a couple hundred miles as the cats wore in.
MagnaFlow 93419 Direct Fit Catalytic Converter
thoughts on this replacement kit if it is indeed the cats?
not sure i just looked at the best rated ones real quick. looking at that video rhe S2 jumping is actually the one thts off? but off in a wat showing cat damage or o2 sensor damage?