Code 172 ALWAYS O2 sensors?

[justakid]

I have a 94' ATX SHO with 190k miles. My CE light will come on from time to time for anywhere from 5 secs to a few minutes. I ran the codes and got "172 system running lean" or something to that effect. I did a search here and saw that it was most likely O2 sensors. So I speak with my father about it (as this was his SHO until 10k miles ago..). He tells me he got the same code about 40k miles ago and replaced the O2 sensors and then about 2 weeks later it started again (and has ever since). So my question is how likely is it that this 172 is being caused by something other than my O2 sensors? Or is my dad on crack?

Thanks in advance,
Wes

 

[sdpatt]

Code 172 is defined by
Dali Design as the following.

172 (R,M) Oxygen sensor not switching - system is or was lean - Single, Right or Rear HO2S

Did your dad replace both O2 sensors? What brand and part number of sensor did he install?

The rear bank sensor is up on the exhaust pipe, above the catalytic converter and a pan in the **** to access on the ATX SHO. If only one sensor is showing a rich or lean code it normally indicates a sensor malfinction. If both sensors are reading the same condition you have to think that there truly is a problem with the engine control system and the condition does exist.

With only the rear bank showing lean, and if both sensors were replaced, there could be an oxygen leak at the rear intake manifold either at the intake plenum (vacuum hose connections) or intake runners (rubber connectors, hose clamps, intake to head gasket seal or fuel injector seals). You have some inspecting to do, but first ask your dad what he did for the rear O2 sensor.

 

[BlackOnBlackATX]

i got the O2 error from having a clogged EGR valve and clogged EGR ports in my intake. so its not necessarily your O2 sensors. an EGR valve for us is around 60-70 dollars i think, so not cheap but needed none-the-less. im not sure how to test them though so maybe someone else will lend a hand. you should check out the procedure fo decarboning your intake though, it may turn out to be your problem.

<small>[ March 05, 2003, 02:38 PM: Message edited by: BlackOnBlackATX ]</small>