P0156?

[joshjwc9]

WTF!? Seriously, I am driving home from my GF's house, and all of a sudden the SES light shoots on. I pull over quickly thinking this is another episode in misfires or a plug blowout or something.

It was that code and the usual p1000 only.

Keep in mind I recently installed my Steeda CAI and reinstalled my Diablo 87 tune, plus 1 degree of timing throughout the Rev range and 1 more fuel throughout the rev range.

In my searching on google, here, and the corral the closest thing I can come up with is my MIL option somehow got turned off, the sensor is going bad or the wiring damaged or there is water somewhere in a plugwell.

I just got home from this and believe that it is the latter because of the amount of rainfall we have had in the past couple of days.

I cleared the code and the car ran perfectly fine the approx. 10 miles home.

We will see tomorrow in my errands and going to work.

 

[joshjwc9]

Didn't come on until some heavy rain here in FL over the past few days. Came on again. I think it is just some issues with the wiring...

The car doesn't have MIL eliminators, just the rear o2's are turned off in the Diablo tune.

 

[squeak93]

Its the heated circuit on the d/s rear o2. Wish I could tell you how to fix it as I have the same code on my car (with mil's).

 

[joshjwc9]

In my Diablo, I believe there is an option to turn off the downstream sensors in some way or another. The car is at the tire shop now getting my 10th Anny Cobra's put on otherwise I would be messing with my Diablo tuner.

Does the code affect the o2's functionality? I am probably going to change the option in the tune if the SES light goes off again with that.

 

[hotcobra03]

po156

that code says o2 is bad,,,i would swith the 2 rear o2s left to right and see if code changes to po141...


this is the heater circuit...with car off and exhaust cold...hold hand on o2 sensor body ,than have someone turn the key to the run position,,,the o2`s should start to get hot,,,they have a heater inside of them...

i also have a predator and you can watch the volt readings of you o2`s .. and than you will see what is happinging,,,

take notes than when you replace it you can see what a good one does......i had a front one go bad on the heater circuit also....


fwiw ..on the rear o2`s the blue plug is for left sensor and the purple is for the right,,,when wrong you will get a code,,

 

[squeak93]

I thought you said the rear 02's were already off? If they are not then turn them off. If they are, then your in the same boat as me.

And rear o2's only tell the computer if the cats are working, they do NOT effect performance or mileage at all. So a cel from them is just annoying, not bad.

 

[hotcobra03]

rear o2`s

I thought you said the rear 02's were already off? If they are not then turn them off. If they are, then your in the same boat as me.

And rear o2's only tell the computer if the cats are working, they do NOT effect performance or mileage at all. So a cel from them is just annoying, not bad.

squeak,,,with the predator they can be turned off,,but it is a 2 step...the heaters are seperate and need to be turned off along with the switching...

 

[joshjwc9]

Yes, they are turned off in the OBD2 test so they don't throw a Catalyst Inefficiency Code.

So, do I need to turn them off (the heater circuit in the Diablo) and buy a new o2 sensor?

 

[the98stang]

Yes, they are turned off in the OBD2 test so they don't throw a Catalyst Inefficiency Code.

So, do I need to turn them off (the heater circuit in the Diablo) and buy a new o2 sensor?

Just turn off both rear (heated) o2 sensors. They don't serve any real purpose or affect performance. It should stop throwing the code once you turn them off. It's the front o2's that send a signal to the PCM.

 

[squeak93]

squeak,,,with the predator they can be turned off,,but it is a 2 step...the heaters are seperate and need to be turned off along with the switching...

I see. I obviously don't have a predator...