From: Vic Smith on
On Thu, 17 Jun 2010 10:10:29 -0700 (PDT), ben91932
<benteaches(a)> wrote:

>On Jun 15, 8:33 pm, Vic Smith <thismailautodele...(a)> wrote:
>> When we got around to the Eclipse the kid found 4 sensors on it and we
>> were basically lost until I plugged the codes into google.  Turned out
>> the 3 codes were really for the left and right downstream sensors.
>With no intention of sounding preachy or patronizing, I sure hope that
>the 02's are the problem.
>The downstream 02's are there to measure catalytic converter
>efficiency.. so if the cats are compromised the 02's wont help.
>When chasing those codes, I always check the cats with an infrared no-
>touchy thermometer... after running for 3 minutes at 2000 rpm
>the outlet of the cat should be at least 75 degrees hotter than the
>Hope this helps

Thanks for the thermometer/cat tip.
All the excuse I need to buy an infrared thermometer.
I mentioned this to my son and he doesn't have one so I'll surprise
him with one for his tool chest.
The codes themselves are pretty clear.
PO136 o2 sensor circuit malfunction (Bank 1 sensor 2)
P0141 o2 sensor heater circuit malfunction (Bank 1, Sensor 2)
PO156 o2 sensor circuit malfunction (Bank 2 Sensor 2)

These sensors supposedly have a 100k mile lifetime, and the car is
right about there.
There are threshold codes that are supposed to show for a bad cat, I
think from measuring the upstream versus downstream.
But I'll take your advice and measure the cat temps before we put new
sensors in the cats.
Good test for the new thermometer (-:
Thanks again.


ps Speaking of chasing codes, my son's buddy was over the other day
and my son read his Audi A6, which was throwing an intermittent code.
No info on the code from the reader, just the code. I don't remember
the code.
We googled that and found it for about 4 different brands of cars, and
it was always TPS or pedal sensor.
The kids were ready to go out and look for a wire problem on the TPS
as a starting point.
I said keep looking until you find the code with the Audi A6.
They kept digging and found that for the Audi the code was for an o2
hehe. What do they say about assumptions?
And I think that was a PO prefix code, which are supposed to be