I have a 99 integra gsr running hondata s300 v2
I was trying to install a wideband sensor which made me unplug the D connector on the ecu and I started the engine without plugging back in the D connector (my fault) it ran for about 5 seconds terribly. I realized and plugged it back in then tried to start it again and it wouldn't start it just smelt like gas, so I took the plugs out and sure enough they were wet. I bought new plugs and started it with my foot all the way to the floor so it should turn the injectors off and it did start but was back firing terribly and wouldn't rev over 1.5k rpm. It would sound normal but wouldn't idle under 1.5k rpm it sounds like I am hitting 2 step when I go over 1.5-2k rpm. also my afr is reading 8.2 which is super rich I don't know if a sensor blew out or what but it doesnt want to run anymore It worked perfectly before. I forgot to mention that one time I got it to run really good Idk what I did but somehow it cleared up and ran good until I shut it off and once I started it back up it just did the same thing but would clear up.

Spark plug cables are on right
New plugs

 

Do you have a laptop?

Was the engine tuned? And if so, was it in open or closed loop?

I'm guessing you're running the car in open loop at all times, since you added a AFR gauge you might need to check if the engine is running in open loop or closed loop now. Closed loop is better to be in...

Getting gas at different gas stations, and different brands, can have more than 5% change in fuel delivery requirements. That's why o2 sensors exist, to compensate for variables like this. Run the car in closed loop and let the fuel trims do the adjustments for you, AFTER you make sure IAT and ECT compensations are dialed in properly so make sure you make the correct adjustments in S300 for the AFR gauge.