Re: RE V8 dangling wires

[Steve Manning <stephenm@ix.netcom.com>]

At 07:30 PM 1/3/98 -0500, you wrote:
>Listers- In late Dec while replacing a CV boot, I noticed two unconnected
>plugs on the drivers side inside the engine compartment. Joe Y. thought they
>might be associated with the brake sensors. After further inspection I
>concluded they were test connectors for the tranny, but promised to update
>you if this was a bad call. Well I traced the wires and they went to the O2
>sensor in the exhaust system. After much searching, I located the mating
>jacks on the engine under the distributor/cruise control bellows. After
>reconecting the car seems to have a bit more pep, and idles 150rpm lower. I
>have been runing without an O2 sensor for many months. Can anyone explain how
>this was possible? American cars won"t even start with the O2 sensor
>disconnected.
>Frank Santoro (FBFISH@aol.com)
>Kingsville Md
>1990 V8

Most cars will run without an O2 sensor....they all run that way (open
loop) until the sensor gets warm enough to send a signal.  That's one
reason why most O2 sensors are heated...to get them up to temp and working
sooner.  Without a signal from the O2 sensor you were running a default
map, which is non-optimized...when you put the O2 sensor back in it could
finally control mixture real-time and provide a better idle and power.

I'd check the sensor to see if it was disconnected because it was acting
up...if it's original w/more than 60k miles I'd just replace it.  V8's are
finicky about the O2 sensor; sometimes they only last 30k miles.  You'll
notice a surging in acceleration as a first sign of problems.  I'd also
worry somewhat about the cat getting plugged if it was run a long time w/o
the O2 sensor.

By the way, did you pull the codes?  You should have had an error code set
when the ECU determined that it should be getting a signal from the O2
sensor and wasn't getting one............SLM

Steve Manning:  stephenm@ix.netcom.com
...Physical home: Metro D.C. area, USA
.....Virtual home:  http://www.stationwagon.com