Rep Power: 0

few months back i replaced the upstream and downstream o2 sensors and my car was running a little jumpy but it soom subsided. now, my car is almost stalling when i go to drive off on a red light, this also happens when i’m starting my car when it’s warm, it’ll almost stall then go settle at a reasonable idle rpm. my question is for the upstream sensor, is it an o2 sensor or an A/F ratio sensor? my engine is throwing a code for my upstream sensor but my downstream seems to be working fine. im
not much of a car guy so i could really use some help on this.
Also if it helps, my car does seem to have a bit of hesitation when accelerating soemtimes. I also don’t know if it’s just cuz my cars slow but when i’m tryna accelerate, it seems very sluggish. like my i have my peddle bit more than halfway down and it seems to just stick around 3-4k rpm and i gotta almost put my peddle to the floor so get it to go lol
Engine info:
2005 Civic LX sedan
1.7L SOHC I4 (no vtec)

 
Rep Power: 511

Upstream is indeed an a/f ratio sensor. A wideband, to be specific. They changed to wideband afr sensors from narrow in 2004. The downstream is just to check cat function