forwardtocharis

I searched around and I didn't see this problem and I think it's a little more complicated than "replace the o2 sensor"
My engine's running super rich. My Air/Fuel gauge reads totally lean. My old os sensor read .02v, my new one read .05v (normal range is .25 - .8). So pretty far off.
Now this is where it gets tricky, I stuck one of the o2 sensors in the tail pipe to get a reading, more than anything just to see if it was doing anything at all. When I pulled it out it was covered in gas.
So my theory is that there is so much fuel going straight through my engine that it's knocking out the o2 sensor. The problem is that the lack of a reading from the o2 sensor is causing the problem (ie: if I put another new one in it would go out on me just as fast because the ecu is used to sending in massive amounts of fuel). So the problem then is rather circular. I thought about rigging up a device to output .5v till the engine leaned out and then swap in a new sensor, but I really don't want to spend the time on that.
Any other thoughts/ideas? Between this and the fuel leak I've had I'm really sick of the smell of gas.

4Crawler

iTrader: (3)

How are you measuring the output voltage? You either need an analog voltmeter (i.e. one with a needle that swings back and forth) or a very good/fast digital meter since the voltage swings back and forth in the 0.2-0.8 volt range once a second or so. Also test must be done hot, RPMs at 2500 or so for a few minutes, since the sensor in the '85 is unheated. One option is to retrofit a heated sensor in there.

forwardtocharis

I just reread the operation of the o2 sensor and now I'm more puzzled. So my engine is obviously running rich, but the o2 sensor is recording low voltage. I had used a cheap digital multimeter, but I might try it with an analog meter today, measurments were done hot. Apart from that I have my air-fuel ratio gauge which has been reading absolute lean, but absolute lean should be around .8v (I forget what the gauge is spec'ed at).
So, I have 2 o2 sensors, one that was working, and then stopped showing any reading on my gauge and one that is "new" that never showed any reading on my gauge. The engine is running ridiculously rich. It's possible that some of this came about post-installation of a supra afm.
I know disconnection the ecu for a while can reset most of its "learned" standards, think it might help? Also, what of my o2 sensors? are either salvageable?

dinahcat

I replaced the head gaskets and when I started the engine it ran for approx. 2 to 3 miniutes. It than flooded out with gas dripping out of the exhaust pipe.I tried it again after switching some of the vacuum tubes around on the power steering side. Neither Hayes or Chilton have specific diagrams for these hoses.Is the problem in these hoses or elsewhere?