Help with front bank upstream O2 sensor

[DeltaP]

Originally Posted by dylanborns

Ok, so I had it reread and it is the front upstream sensor. I checked the wiring and it doesn't look to be damaged from when I worked on it, but I can't really see the top of the sensor where the wiring connects. If there is damage to it, thats probably where it would be since I was using the socket right there.

I'm not able to get to this in the next week, so besides possibly having lower gas mileage, what will driving this cause if I wait about a week?
I know that these things are heated for some reason, but what exactly is a "Heater Circuit Malfunction"?

Not much more than that. The heater allows the sensor to get "on line" with the CCM faster in order to obtain "closed loop" operation sooner.
A "malfunction" is usually an open or shorted circuit in the wiring or sensor.

[dylanborns]

Well, here is the SOB that I couldn't get out..


My last attempt at doing this myself had me going to three different hardware stores looking for a stubby socket wrench. I couldn't find a shorter one in 3/8", so I bought a 6" crescent wrench that would fit a 7/8" nut. I tried it, but still didn't have enough room to turn it. There is a vertical support bar that runs up the middle of the car that gets in the way. Its only held in by a half dozen screws, and if removed would probably allow for a wrench to be turned, but the hood latch assembly is connected to it. You would have to remove the assembly to get that support out.
So while I'm feeling around to get the crescent wrench on the sensor, I noticed it felt loose. At first I thought it was just the top part of the sensor, but then noticed it was turning out! I must have actually got it loosened the last time I worked on it and didn't notice, or maybe with driving it as I have, the hot/ cold loosened it. With it being loose, thats probably why I got the check engine light because the wiring and sensor looked intact.
It was a little difficult getting the new one lined up but I found that if you get it started in the hole, and take a flashlight looking down from the top of the motor, you can just barely see it. I was then able to tell if I was inline with the bung and make adjustments to line it up. I couldn't get my arm down to it from the top, so get it started from the bottom then see if its lined up from the top and make adjustments from the bottom.

[DeltaP]

Did you fix the problem?

[dylanborns]

Did you fix the problem?

I've put about 50 miles on it since I replaced that last sensor and have had no issues. No check engine light yet!