Help P1139??

Does anyone have any info on this code (P1139)?

Thanks in advance.

Check this link, of course we guessed at the year! Direct fom GM, don't see the code though, http://service.gm.com/gmspo/mode6/pdf/2000/2000file10.pdf

The '96 book says :
DTC P1139 is designed so that if the O2 sensor is slow to respond
to changes in exhaust content,then DTC P1139 will set.
There are 4 O2 sensors in the '96 4.0L

If the sensor is bad it is located under the passenger compartment
It is bank 1 Sensor 2, The pre-converter O2 Sensor

[QUOTE=apollo7879]The '96 book says :
DTC P1139 is designed so that if the O2 sensor is slow to respond
to changes in exhaust content,then DTC P1139 will set.
There are 4 O2 sensors in the '96 4.0L

If the sensor is bad it is located under the passenger compartment
It is bank 1 Sensor 2, The pre-converter O2 Sensor


Thanks apollo7879 for the info. How can tell if the sensor is bad? Should I just change the (auto zone $69.00) sensor? If I cleaned the egr valve would that do anything?

Sorry for all the questions. Thanks again

I don't think the EGR valve will clear this code.(But if you haven't ever cleaned the valve you should anyway)
Does the car run ok, or does it seem to surge & run a little rough.
That is the condition that I had(along with the "check engine lite")
and I think i had the same P1139 code. At any rate I replaced the
sensor & it solved my problem.
The sensor is easy to change, with the loaned sensor wrench from AutoZone.
I guess the question is: how is the car running?