I have a 93 Supra na 4 speed auto no mods. When I first got the car the rpm were high around 1500-2000 I thought it was the fuel injection idle control valve so I went to junkyard and got a used one. Once I plugged it in the rpm dropped to 900-1000. I was able to drive the vehicle with no issues it would shift normally. But after a few miles the rpm would drop to around 600-700 and there would be no power when I would hit the gas. in fact it would like almost want to stall when I hit the gas. I could see my fuel gauge start dropping and I could smell gas. So I'm guessing I'm running rich. I couldn't even tell him car would shift while I was driving because of the lack of power. When I arrived home I shut it off then after a few min I would start it up again and it would turn on just fine no issues. I popped the hood and unplugged the fuel injection idle control valve and the car did nothing. It still ran just fine. I don't know if I should just buy a new sensor to see if that's the case since the one I put in was a used one from junkyard. Or if there could be something else wrong with the car?