2005 Lexus LS 430 UL with 190k Miles:

Initial Problem developed few months ago when Check Engine Light came on, Took it to a local Autozone to understand the Code.
It was clearly Bank 1 Sensor 1 Code, So i went ahead and got both Upstream Denso Sensors (Bank 1 & Bank 2)

Took it to local Exhaust/Muffler shop to get the Sensors replaced, One thing i noticed when i picked up the car that Interior Lights, HVAC Controls (Physical buttons)/Audio was not working.
2 Miles down the road, Check Engine Light along with Trac off came back on again.

Once i got home, i was able to fix interior lights/Audio by replacing one of the Fuses...It was evident that Muffler Shop shorted out the circuit that led to blown fuse.

Fast forward few months later, i took it to a different Exhaust shop all together to have a look...They came back and said Passenger Upstream Harness is all taped up and they are not seeing any Readings from the Sensor.
At this point, they suggested we fix the wire...Install New Upstream Sensors (Driver side & passenger side)....Went ahead and did that

Shop Re-verified to ensure Readings are in line with what they should be....However, Light came back on within 2-3 miles.

Note: Car does feel like it's going to choke if i step on it hard (In Drive)....At Idle, I can rev all the way to 5-6k RPM without issues.

Any pointers as to what it could possibly be?

• Is it possible that ECM is bad?
• Could the car choke when stepping on it due to Ignition Coils?

Car does have all Fresh Fluids, New PCV, New Spark Plugs...etc