Vehicle is a 1989 toyota pickup, shortbed, 22re. SASD and all kinds of fun stuff.
First question, the fuel pump stays on no matter the key position. We pulled a circular relay looking thing off the fuse board under the hood and it stopped. Is it a relay or somethin?
Second question, would an O2 sensor too close to the head on the exhaust cause a false lean and make the engine run rich?
The dip but the O2 sensor about 5 inches from the header flange to the head. Seems a bit close.

What's the average pis one of these fuel pumps should run?

 

Sounds like the contacts are stuck on your relay.

Or something else is telling the fuel pump to stay on

Fuel pressure should be between 33 to 44 psi at idle in that range depending if the vacuum hose is on or off.

 

What about the o2 sensor?

 

when you pull the relay out ...do you hear the coil drop out ? try plugging it in and pulling it out a few times.....if you hear a slight ping noise.... it means something is calling the relay to pick.. would have to hit the manual for ignition wiring schematics for that......if not the relay its self is stuck closed .......

 

We fixed the relay, just bought a new one.
It was activating the fuel pump.
Just need to know about the o2 sensor

 

It doesnt seem like it would be too close in my opinion, unless the wires are burned or chafed it shouldnt change the readings, all the readings will come from the probe on the inside. Is there any exhaust leaks or anything, that would cause a false lean, the sensor could also be bad, if you pull it out and the probe is covered in soot and black then it is probably a bad or slow sensor. Do you have a pic to give us a better idea of what it looks like?

 

We pulled it, it was black and sooty.
Were gonna cut the flange and move it back behind the collector so it reads off all 4 cylinders and is in a "cooler" spot. The wires got melted and chafed in the spot they were in, but the parts rig had all the wiring so we stole that.
Hopefully a new o2 sensor fixes it.

 

I have cleaned these o2 sensors on a wire wheel and had them work fine again.

I think you will be good to go moving it to the new location .

 

Hopefully it works. Thanks.